In multi-user mode, x-harness-api-key is required on initialize.

Harness MCP Server 2.0

An MCP (Model Context Protocol) server that gives AI agents full access to the Harness.io platform through 11 consolidated tools and 218 resource types.

Why Use This MCP Server

Most MCP servers map one tool per API endpoint. For a platform as broad as Harness, that means 240+ tools — and LLMs get worse at tool selection as the count grows. Context windows fill up with schemas, and every new endpoint means new code.

This server is built differently:

• 11 tools, 218 resource types. A registry-based dispatch system routes harness_list, harness_get, harness_create, etc. to any Harness resource — pipelines, services, environments, orgs, projects, feature flags, cost data, and more. The LLM picks from 11 tools instead of hundreds.
• Full platform coverage. 38 default toolsets spanning CI/CD, GitOps, Feature Flags, Cloud Cost Management, Security Testing, Chaos Engineering, Database DevOps, Internal Developer Portal, Software Supply Chain, Infrastructure as Code Management, Governance, Service Overrides, Knowledge Graph, Visualizations, and more. Opt-in Ansible coverage is available when you need inventory and playbook data.
• Multi-project workflows out of the box. Agents discover organizations and projects dynamically — no hardcoded env vars needed. Ask "show failed executions across all projects" and the agent can navigate the full account hierarchy.
• 32 prompt templates. Pre-built prompts for common workflows: build & deploy apps end-to-end, debug failed pipelines, review DORA metrics, triage vulnerabilities, optimize cloud costs, audit access control, plan feature flag rollouts, review pull requests, approve pending pipelines, and more.
• Works everywhere. Stdio transport for local clients (Claude Desktop, Cursor, Devin Desktop), HTTP transport for remote/shared deployments, Docker and Kubernetes ready.
• Zero-config start. Just provide a Harness API key. Account ID is auto-extracted from PAT and SAT tokens, org/project defaults are optional, and toolset filtering lets you expose only what you need.
• Extensible by design. Adding a new Harness resource means adding a declarative data file — no new tool registration, no schema changes, no prompt updates.

Prerequisites

Before installing or running the server, you need a Harness API key:

1. Log in to your Harness account
2. Go to My Profile → API Keys → + New API Key
3. Create a new Token under the API key — this generates a PAT or SAT in the format <prefix>.<accountId>.<tokenId>.<secret>
4. Save the token somewhere secure — you'll need it in the next step

For detailed instructions, see the Harness API Quickstart.

Quick Start

Option 0: Hosted Harness MCP

If your Harness account has the hosted MCP service enabled, clients that support remote MCP servers can connect directly to the managed endpoint instead of running the server locally.

Important: The hosted MCP service uses Harness Platform OAuth, not HARNESS_API_KEY. It must also be enabled/configured per account by Harness Support before the endpoint can be used.

See Hosted Harness MCP for configuration examples.

Option 1: npx (Recommended)

No install required — just run it:

HARNESS_API_KEY=pat.xxx.xxx.xxx npx harness-mcp-v2@latest

Or configure the API key in your AI client (see Client Configuration below).

# Stdio transport (default — for Claude Desktop, Cursor, Devin Desktop, etc.)
HARNESS_API_KEY=pat.xxx npx harness-mcp-v2

# HTTP transport (for remote/shared deployments)
HARNESS_API_KEY=pat.xxx npx harness-mcp-v2 http --port 8080

Note: The account ID is auto-extracted from PAT and SAT tokens (pat.<accountId>... or sat.<accountId>...), so HARNESS_ACCOUNT_ID is only needed for API keys without an embedded account segment.

Option 2: Global Install

npm install -g harness-mcp-v2

# Then run directly
harness-mcp-v2

Option 3: Build from Source

For development or customization:

git clone https://github.com/harness/mcp-server.git
cd mcp-server
pnpm install
pnpm build

# Run
pnpm start              # Stdio transport
pnpm start:http         # HTTP transport
pnpm inspect            # Test with MCP Inspector

Anthropic MCP Directory bundle

The MCPB bundle manifest lives in [mcp-directory/](mcp-directory/), and the bundle icon is tracked at [icon.png](icon.png) in the repository root. Copy mcp-directory/manifest.json to the bundle root after pnpm build so the generated archive contains root-level manifest.json, icon.png, build/, package.json, and production node_modules/.

To keep the archive small, build MCPB packages from a staging directory:

pnpm prepare:mcpb

The staged package is written to dist/mcpb/ with production dependencies installed using npm's flat layout.

CLI Usage

harness-mcp-v2 [stdio|http] [--port <number>]

Options:
  --port <number>  Port for HTTP transport (default: 3000, or PORT env var)
  --help           Show help message and exit
  --version        Print version and exit

Transport defaults to stdio if not specified. Use http for remote/shared deployments.

HTTP Transport

When running in HTTP mode, the server exposes:

Endpoint	Method	Description
/mcp	POST	MCP JSON-RPC endpoint (initialize + session requests)
/mcp	GET	SSE stream for server-initiated messages (progress, elicitation)
/mcp	DELETE	Terminate an active MCP session
/mcp	OPTIONS	CORS preflight
/health	GET	Health check — returns { "status": "ok", "sessions": <count> }

The HTTP transport runs in session-based mode. A new MCP session is created on initialize, the server returns an mcp-session-id header, and subsequent requests for that session must include the same header.

Operational constraints in HTTP mode:

• Set HARNESS_MCP_AUTH_TOKEN for any shared or remotely reachable deployment. When set, every POST, GET, and DELETE request to /mcp must include Authorization: Bearer <token>.
• Non-loopback binds require HARNESS_MCP_AUTH_TOKEN by default. To run unauthenticated on a non-loopback interface anyway, set HARNESS_MCP_ALLOW_UNAUTHENTICATED_HTTP=true explicitly.
• POST /mcp without mcp-session-id must be an initialize request.
• POST /mcp, GET /mcp, and DELETE /mcp for existing sessions require the mcp-session-id header.
• GET /mcp is used for SSE notifications (progress updates and elicitation prompts).
• Idle sessions are reaped after 30 minutes.
• GET /health is the only non-MCP endpoint.
• Request body size is capped by HARNESS_MAX_BODY_SIZE_MB (default 10 MB).
• Set x-harness-pipeline-version: 0 or 1 on the initialize request to select V0 or V1 pipeline resources for that HTTP session.
• Set x-harness-auto-approve-risk: none|low_write|medium_write|high_write|all on the initialize request to choose a stricter per-session auto-approval threshold. The server caps this value at the deployment-level HARNESS_AUTO_APPROVE_RISK, so a session can reduce but not expand the configured approval ceiling.

Multi-User Mode

Set HARNESS_MCP_MODE=multi-user for shared HTTP deployments where each client authenticates as a different Harness user. In this mode:

• HARNESS_API_KEY must not be set in the server config — the server holds no Harness credentials.
• Each session must provide x-harness-api-key on the initialize request. x-harness-account-id is required only when the API key does not embed an account segment.
• Sessions may also provide x-harness-org and x-harness-project headers to set default scope for that session.
• The Harness API key flows through to every Harness API call for that session, so the audit trail in Harness reflects the real user.
• HARNESS_MCP_AUTH_TOKEN is independent and can still be used as an additional transport-layer gate.

# Health check
curl http://localhost:3000/health

# MCP initialize request (capture mcp-session-id response header)
# In multi-user mode, x-harness-api-key is required on initialize.
# x-harness-account-id is needed only for API keys without an embedded account segment.
curl -i -X POST http://localhost:3000/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -H "Authorization: Bearer $HARNESS_MCP_AUTH_TOKEN" \
  -H "x-harness-api-key: $HARNESS_API_KEY" \
  -H "x-harness-account-id: $HARNESS_ACCOUNT_ID" \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-03-26","capabilities":{},"clientInfo":{"name":"test","version":"1.0"}}}'

# Subsequent MCP request (use returned session ID)
curl -X POST http://localhost:3000/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -H "Authorization: Bearer $HARNESS_MCP_AUTH_TOKEN" \
  -H "mcp-session-id: <session-id>" \
  -d '{"jsonrpc":"2.0","id":2,"method":"tools/list","params":{}}'

# Terminate session
curl -X DELETE http://localhost:3000/mcp \
  -H "Authorization: Bearer $HARNESS_MCP_AUTH_TOKEN" \
  -H "mcp-session-id: <session-id>"

HARNESS_MCP_ALLOWED_HOSTS controls Host-header validation for DNS-rebinding protection, and CORS limits browser origins. Neither is authentication; use HARNESS_MCP_AUTH_TOKEN or an authenticated gateway/reverse proxy for access control.

Client Configuration

Note: HARNESS_ORG and HARNESS_PROJECT are optional. They set the org ID and project ID used when not specified per tool call. Agents can discover orgs and projects dynamically using harness_list(resource_type="organization") and harness_list(resource_type="project"). The deprecated names HARNESS_DEFAULT_ORG_ID and HARNESS_DEFAULT_PROJECT_ID are still accepted for backward compatibility.

Hosted Harness MCP

Harness also supports a hosted MCP endpoint for accounts that have the managed service enabled. This is useful when you want a shared remote MCP endpoint instead of running npx harness-mcp-v2 or self-hosting the HTTP transport yourself.

Important: Hosted MCP authentication uses Harness Platform OAuth. It does not use HARNESS_API_KEY in the client config. Hosted MCP availability is configured per Harness account, so you will need to work with Harness Support to enable/configure the setting before using it.

The hosted endpoint https://mcp.harness.io/mcp is a managed service. Client-side MCP config in Claude, Cursor, or Cowork cannot override which Harness environment it routes to. For Harness0 or another private Harness SaaS environment, ask Harness Support to enable/configure hosted MCP for that environment, or run the local/self-hosted server and set HARNESS_BASE_URL to the target Harness host.

Hosted MCP example:

{
  "mcpServers": {
    "harness-prod1-mcp": {
      "url": "https://mcp.harness.io/mcp",
      "auth": {
        "CLIENT_ID": "mcp-client"
      }
    }
  }
}

Example with both hosted and local entries:

{
  "mcpServers": {
    "harness-hosted": {
      "url": "https://mcp.harness.io/mcp",
      "auth": {
        "CLIENT_ID": "mcp-client"
      }
    },
    "harness-local": {
      "command": "/absolute/path/to/npx",
      "args": ["-y", "harness-mcp-v2@latest"],
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx",
        "PATH": "/directory/containing/node:/usr/local/bin:/usr/bin:/bin"
      }
    }
  }
}

Troubleshooting npx ENOENT or node: No such file or directory

This is a client process-launch failure, not a Harness authentication failure. The MCP server has not started yet, so changing HARNESS_API_KEY will not affect spawn npx ENOENT.

GUI apps (Cursor, Claude Desktop, Devin Desktop, VS Code) don't always inherit your shell's PATH, so they can fail to find npx or node after a config reload. Fix this by using absolute paths and explicitly setting PATH in the env block:

{
  "mcpServers": {
    "harness": {
      "command": "/absolute/path/to/npx",
      "args": ["-y", "harness-mcp-v2"],
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx",
        "PATH": "/opt/homebrew/bin:/usr/local/bin:/usr/bin:/bin"
      }
    }
  }
}

Find your paths with which npx and which node in a terminal, then make sure the directory containing node is included in the PATH value above. Common locations:

• Homebrew (macOS): /opt/homebrew/bin/npx
• nvm: ~/.nvm/versions/node/v20.x.x/bin/npx (run nvm which current to find the exact path)
• System Node: /usr/local/bin/npx

Claude Desktop (claude_desktop_config.json)

npx (zero install)

{
  "mcpServers": {
    "harness": {
      "command": "/absolute/path/to/npx",
      "args": ["-y", "harness-mcp-v2@latest"],
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx",
        "PATH": "/directory/containing/node:/usr/local/bin:/usr/bin:/bin"
      }
    }
  }
}

node (local install)

npm install -g harness-mcp-v2

{
  "mcpServers": {
    "harness": {
      "command": "/absolute/path/to/harness-mcp-v2",
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx",
        "PATH": "/directory/containing/node:/usr/local/bin:/usr/bin:/bin"
      }
    }
  }
}

Claude Code (via claude mcp add)

npx (zero install)

claude mcp add harness -- npx harness-mcp-v2

node (local install)

npm install -g harness-mcp-v2
claude mcp add harness -- harness-mcp-v2

Then set HARNESS_API_KEY in your environment or .env file.

Cursor (.cursor/mcp.json)

npx (zero install, recommended for local Cursor configs)

{
  "mcpServers": {
    "harness": {
      "command": "/absolute/path/to/npx",
      "args": ["-y", "harness-mcp-v2@latest"],
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx",
        "PATH": "/directory/containing/node:/usr/local/bin:/usr/bin:/bin"
      }
    }
  }
}

Run which npx in a terminal and use that full path for command; include the directory from which node at the front of PATH.

node (local install)

npm install -g harness-mcp-v2

{
  "mcpServers": {
    "harness": {
      "command": "/absolute/path/to/harness-mcp-v2",
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx",
        "PATH": "/directory/containing/node:/usr/local/bin:/usr/bin:/bin"
      }
    }
  }
}

Run which harness-mcp-v2 after npm install -g harness-mcp-v2 and use that full path for command; include the directory from which node at the front of PATH.

Devin Desktop (~/.windsurf/mcp.json)

npx (zero install)

{
  "mcpServers": {
    "harness": {
      "command": "/absolute/path/to/npx",
      "args": ["-y", "harness-mcp-v2@latest"],
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx",
        "PATH": "/directory/containing/node:/usr/local/bin:/usr/bin:/bin"
      }
    }
  }
}

node (local install)

npm install -g harness-mcp-v2

{
  "mcpServers": {
    "harness": {
      "command": "/absolute/path/to/harness-mcp-v2",
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx",
        "PATH": "/directory/containing/node:/usr/local/bin:/usr/bin:/bin"
      }
    }
  }
}

Using a local build from source?

Replace the command with the path to your built index.js:

{
  "command": "node",
  "args": ["/absolute/path/to/harness-mcp-v2/build/index.js", "stdio"]
}

MCP Gateway

The Harness MCP server is fully compatible with MCP Gateways — reverse proxies that provide centralized authentication, governance, tool routing, and observability across multiple MCP servers. Since the server implements the standard MCP protocol with both stdio and HTTP transports, it works behind any MCP-compliant gateway with no code changes.

Why use a gateway?

• Centralized credential management — no API keys in agent configs
• Governance & audit logging for all tool calls across teams
• Single endpoint for agents instead of N connections to N MCP servers
• Access control — restrict which teams can use which tools

Docker MCP Gateway

Register the server in your Docker MCP Gateway configuration:

{
  "mcpServers": {
    "harness": {
      "command": "npx",
      "args": ["harness-mcp-v2"],
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx"
      }
    }
  }
}

Portkey

Add the Harness MCP server to your Portkey MCP Gateway for enterprise governance, cost tracking, and multi-LLM routing:

{
  "mcpServers": {
    "harness": {
      "command": "npx",
      "args": ["harness-mcp-v2"],
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx"
      }
    }
  }
}

LiteLLM

Add to your LiteLLM proxy config:

mcp_servers:
  - name: harness
    command: npx
    args:
      - harness-mcp-v2
    env:
      HARNESS_API_KEY: "pat.xxx.xxx.xxx"

Envoy AI Gateway

The server works with Envoy AI Gateway's MCP support via HTTP transport:

# Start the server in HTTP mode
HARNESS_API_KEY=pat.xxx.xxx.xxx npx harness-mcp-v2 http --port 8080

Then configure Envoy to route to http://localhost:8080/mcp as an upstream MCP backend.

Kong

Use Kong's AI MCP Proxy plugin to expose the Harness MCP server through your existing Kong gateway infrastructure.

Other Gateways

Any gateway that supports the MCP specification (Microsoft MCP Gateway, IBM ContextForge, Cloudflare Workers, etc.) can proxy this server. For stdio-based gateways, use the default transport. For HTTP-based gateways, start the server with http transport and point the gateway at the /mcp endpoint.

Docker

Build and run the server as a Docker container:

# Build the image
pnpm docker:build

# Run with your .env file
pnpm docker:run

# Or run directly with env vars
docker run --rm -p 3000:3000 \
  -e HARNESS_API_KEY=pat.xxx.xxx.xxx \
  -e HARNESS_ACCOUNT_ID=your-account-id \
  harness-mcp-server

The container runs in HTTP mode on port 3000 by default with a built-in health check.

Kubernetes

Deploy to a Kubernetes cluster using the provided manifests:

# 1. Edit the Secret with your real credentials
#    k8s/secret.yaml — replace HARNESS_API_KEY and HARNESS_ACCOUNT_ID

# 2. Apply all manifests
kubectl apply -f k8s/

# 3. Verify the deployment
kubectl -n harness-mcp get pods

# 4. Port-forward for local testing
kubectl -n harness-mcp port-forward svc/harness-mcp-server 3000:80
curl http://localhost:3000/health

The deployment runs 2 replicas with readiness/liveness probes, resource limits, and non-root security context. The Service exposes port 80 internally (targeting container port 3000).

Configuration

The server automatically loads environment variables from a .env file in the project root if one exists. Copy .env.example to .env and fill in your values. Environment variables can also be set via your shell or MCP client config.

Variable	Required	Default	Description
HARNESS_MCP_MODE	No	single-user	Deployment mode: single-user (API key in config, used for all sessions) or multi-user (HTTP only, per-session credentials via x-harness-api-key and optional x-harness-account-id headers)
HARNESS_API_KEY	Yes*	--	Harness personal access token or service account token. Required in single-user mode. Must NOT be set in multi-user mode
HARNESS_ACCOUNT_ID	No	(from PAT/SAT)	Harness account identifier. Auto-extracted from PAT/SAT tokens in single-user mode; multi-user sessions can provide their own via x-harness-account-id when the API key does not embed one
HARNESS_BASE_URL	No	https://app.harness.io	Harness API/UI base URL for local stdio or self-hosted HTTP deployments. Set this to environments such as https://harness0.harness.io when running the server yourself. It does not affect the managed https://mcp.harness.io/mcp hosted endpoint
HARNESS_FME_API_KEY	No	--	Optional single-user/self-hosted FME/Split Admin credential used for fme_ resources. This can be a legacy Split admin key or an FME-entitled Harness PAT/SAT. FME calls go directly to api.split.io, so hosted OAuth/service-routing credentials for Harness platform APIs do not authenticate these requests. Must not be set in multi-user mode; FME must use each session's x-harness-api-key credential. If unset, FME falls back to a non-placeholder HARNESS_API_KEY for self-hosted sessions
HARNESS_FME_BASE_URL	No	https://api.split.io	Split/FME Admin API base URL used by fme_ resources. HTTP URLs require HARNESS_ALLOW_HTTP=true for local development
HARNESS_ORG	No	--	Organization ID. Used when org_id is not specified per tool call. If omitted, org_id must be provided explicitly. Agents can also discover orgs dynamically via harness_list(resource_type="organization")
HARNESS_PROJECT	No	--	Project ID. Used when project_id is not specified per tool call. Agents can also discover projects dynamically via harness_list(resource_type="project")
HARNESS_API_TIMEOUT_MS	No	30000	HTTP request timeout in milliseconds
HARNESS_MAX_RETRIES	No	3	Retry count for transient failures (429, 5xx)
HARNESS_MAX_BODY_SIZE_MB	No	10	Max HTTP request body size in MB for http transport
HARNESS_RATE_LIMIT_RPS	No	10	Client-side request throttle (requests per second) to Harness APIs
LOG_LEVEL	No	info	Log verbosity: debug, info, warn, error
HARNESS_TOOLSETS	No	(defaults)	Comma-separated toolset list. Empty loads default toolsets. Supports +name to explicitly include opt-in toolsets and -name to remove defaults (see Toolset Filtering)
HARNESS_READ_ONLY	No	false	Block all mutating operations (create, update, delete, execute). Only list and get are allowed. Useful for shared/demo environments
HARNESS_AUTO_APPROVE_RISK	No	none	Risk-based auto-approve threshold for autonomous workflows. Operations at or below this risk proceed without confirmation. Values: none, low_write, medium_write, high_write, all. See Elicitation
HARNESS_SKIP_ELICITATION	No	false	Deprecated — use HARNESS_AUTO_APPROVE_RISK=all instead. Kept for backward compatibility
HARNESS_ALLOW_HTTP	No	false	Allow non-HTTPS HARNESS_BASE_URL. By default, the server enforces HTTPS for security. Set to true only for local development against a non-TLS Harness instance
HARNESS_PIPELINE_VERSION	No	0	(Alpha) Pipeline YAML version. 0 loads the pipeline resource type and excludes pipeline_v1; 1 loads pipeline_v1 and excludes pipeline. HTTP sessions can override this at initialize time with x-harness-pipeline-version: 0 or 1
HARNESS_MCP_ALLOWED_HOSTS	No	--	Comma-separated hostnames allowed by HTTP transport Host-header validation. mcp.harness.io is allowed by default for localhost binds; add proxy/custom domains here
HARNESS_MCP_AUTH_TOKEN	No	--	Bearer token required on /mcp HTTP routes when set. Required by default when HTTP transport binds to a non-loopback host
HARNESS_MCP_ALLOW_UNAUTHENTICATED_HTTP	No	false	Explicitly allow unauthenticated HTTP transport on non-loopback binds. Use only behind another authenticated control
HARNESS_MCP_LOG_FILE	No	~/.claude/harness-mcp.log	File used for stdio disconnect/crash diagnostics when stderr may no longer be available
HARNESS_AUDIT_FILE	No	--	Append audit events to a newline-delimited JSON file for durable local collection
HARNESS_AUDIT_WEBHOOK_URL	No	--	HTTPS endpoint that receives batched audit events. HTTP URLs require HARNESS_ALLOW_HTTP=true for local development
HARNESS_AUDIT_WEBHOOK_TOKEN	No	--	Optional bearer token sent to the audit webhook
HARNESS_AUDIT_WEBHOOK_BATCH_SIZE	No	10	Number of audit events to batch before webhook flush
HARNESS_AUDIT_WEBHOOK_FLUSH_MS	No	5000	Max time to hold audit events before webhook flush
OTEL_EXPORTER_OTLP_ENDPOINT	No	--	Enables OpenTelemetry audit spans when the optional OpenTelemetry packages are installed

HTTPS Enforcement

HARNESS_BASE_URL must use HTTPS by default. If you set a non-HTTPS URL (e.g. http://localhost:8080), the server will refuse to start with:

HARNESS_BASE_URL must use HTTPS (got "http://..."). If you need HTTP for local development, set HARNESS_ALLOW_HTTP=true.

Audit Logging

All registry-dispatched Harness API operations (list, get, create, update, delete, and execute) emit structured audit events when audit sinks are configured. Mutating events include the confirmation path used by elicitation or auto-approval when a confirmation context is present; read events currently omit confirmation metadata. Local metadata and schema discovery tools that bypass the registry, such as harness_describe and harness_schema, are not part of this audit stream. A stderr sink is registered by default but goes through the normal logger and obeys LOG_LEVEL; configure file or webhook sinks for durable audit collection:

• HARNESS_AUDIT_FILE appends newline-delimited JSON events for local collection.
• HARNESS_AUDIT_WEBHOOK_URL posts { "events": [...] } batches to an HTTPS webhook, optionally with HARNESS_AUDIT_WEBHOOK_TOKEN. Failed batches are re-enqueued with bounded capacity and eventually dropped with a warning rather than blocking tool execution.
• OTEL_EXPORTER_OTLP_ENDPOINT enables audit spans when the optional OpenTelemetry peer dependencies are installed. The sink reuses an existing tracer provider when one is registered, otherwise it bootstraps a standalone OTLP exporter.

Each event includes the tool name, resource type, operation, identifiers, timestamp, risk, outcome, HTTP method/path, duration, and confirmation method when applicable. Audit sinks are best-effort telemetry; delivery issues are logged and never replay or change the underlying Harness API operation. For OTel setup details and span attributes, see specs/005-otel-audit-sink.md.

Tools Reference

The server exposes 11 MCP tools. Most API tools accept org_id and project_id as optional overrides — if omitted, they fall back to HARNESS_ORG and HARNESS_PROJECT. harness_describe is local metadata only and does not use org/project scope.

URL support: Most API-facing tools accept a url parameter — paste a Harness UI URL and the server auto-extracts org, project, resource type, resource ID, pipeline ID, and execution ID. harness_describe does not accept url.

Scope support: Resource types with account/org/project variants expose supportedScopes in harness_describe. Pass resource_scope when you need a specific level:

• resource_scope: "account" sends only accountIdentifier.
• resource_scope: "org" sends accountIdentifier and orgIdentifier.
• resource_scope: "project" sends account, org, and project identifiers.

Current multi-scope resources include connector, service, environment, infrastructure, secret, file_store, and template. If resource_scope is omitted, the registry uses the resource's default scope and configured defaults, except resources marked as optional scope may omit org/project unless explicitly passed. Harness URLs can also set the scope automatically when the path contains account-level or project-level context.

Structured output: Every tool declares an MCP outputSchema. harness_list normalizes list-like Harness responses into object-shaped structured content so strict clients can validate it: top-level arrays become { "items": [...], "total": <count>, "page": <page> }, and common wrapper keys such as content, data, body, objects, or features are hoisted to items when needed. The text response still contains the compact JSON payload returned to all clients.

Tool	Description
harness_describe	Discover available resource types, operations, and fields. No API call — returns local registry metadata.
harness_schema	Fetch exact YAML/JSON Schema definitions and examples for creating/updating resources. Pipeline/template schemas are bundled; connector, environment, service, secret, and infrastructure schemas are scope-aware entity schemas fetched from bundled snapshots or NG /yaml-schema. Supports deep drilling via path.
harness_list	List resources of a given type with filtering, search, and pagination.
harness_get	Get a single resource by its identifier.
harness_create	Create a new resource. Supports inline and remote (Git-backed) pipelines. Prompts for user confirmation via elicitation.
harness_update	Update an existing resource. Supports inline and remote (Git-backed) pipelines. Prompts for user confirmation via elicitation.
harness_delete	Delete a resource. Prompts for user confirmation via elicitation. Destructive.
harness_execute	Execute an action on a resource (run/retry pipeline, import pipeline from Git, toggle flag, sync app). Prompts for user confirmation via elicitation. For pipeline runs, use the runtime-input workflow below (supports branch/tag/pr_number/commit_sha shorthand expansion).
harness_search	Search across multiple resource types in parallel with a single query.
harness_diagnose	Diagnose pipeline, connector, delegate, and gitops_application resources (aliases: execution -> pipeline, gitops_app -> gitops_application). For pipelines, returns stage/step timing and failure details; for connectors/delegates/GitOps apps, returns targeted health and troubleshooting signals.
harness_status	Get a real-time project health dashboard — recent executions, failure rates, and deep links.

Schema Lookup Workflow

Use harness_schema before creating or updating YAML-backed resources so agents can copy exact field names and constraints instead of guessing from prose.

• Bundled schemas include pipeline, template, trigger, pipeline_v1, template_v1, trigger_v1, inputSet_v1, overlayInputSet_v1, service_v1, infra_v1, and agent-pipeline.
• Entity schemas include connector, environment, service, secret, and infrastructure. They are scope-aware (account, org, or project) and require org_id/project_id when the selected scope requires them.
• Vendored entity snapshots are used first when they match the runtime account; otherwise the tool falls back to the Harness NG /yaml-schema API and caches the result.
• Omit path for a field/section summary, then pass a dot-separated path to inspect a nested definition.

Examples:

{ "resource_type": "pipeline", "path": "pipeline.stages" }

{
  "resource_type": "connector",
  "scope": "project",
  "org_id": "default",
  "project_id": "payments"
}

Maintainers can refresh the vendored entity snapshots with pnpm sync-entity-schemas when Harness entity YAML schemas change.

Tool Examples

Discover what resources are available:

{ "resource_type": "pipeline" }

List organizations in the account:

{ "resource_type": "organization" }

List projects in an organization:

{ "resource_type": "project", "org_id": "default" }

List pipelines in a project:

{ "resource_type": "pipeline", "search_term": "deploy", "size": 10 }

Get a specific service:

{ "resource_type": "service", "resource_id": "my-service-id" }

Run a pipeline:

{
  "resource_type": "pipeline",
  "action": "run",
  "resource_id": "my-pipeline",
  "inputs": { "tag": "v1.2.3" },
  "wait": true
}

Toggle a feature flag:

{
  "resource_type": "feature_flag",
  "action": "toggle",
  "resource_id": "new_checkout_flow",
  "enable": true,
  "environment": "production"
}

Search across all resource types:

{ "query": "payment-service" }

Diagnose an execution by ID (summary mode — default):

{ "execution_id": "abc123XYZ" }

Diagnose from a Harness URL:

{ "url": "https://app.harness.io/ng/account/.../pipelines/myPipeline/executions/abc123XYZ/pipeline" }

Diagnose connector connectivity:

{ "resource_type": "connector", "resource_id": "my_github_connector" }

Diagnose delegate health:

{ "resource_type": "delegate", "resource_id": "delegate-us-east-1" }

Diagnose a GitOps application (with options):

{
  "resource_type": "gitops_application",
  "resource_id": "checkout-app",
  "options": { "agent_id": "gitops-agent-1" }
}

Get the latest execution report for a pipeline:

{ "pipeline_id": "my-pipeline" }

Full diagnostic mode with YAML and failed step logs:

{ "execution_id": "abc123XYZ", "summary": false }

Summary mode with logs enabled (best of both):

{ "execution_id": "abc123XYZ", "include_logs": true }

Get project health status:

{ "org_id": "default", "project_id": "my-project", "limit": 5 }

List database schemas filtered by migration type:

{ "resource_type": "database_schema", "migration_type": "Liquibase" }

List database instances for a schema:

{ "resource_type": "database_instance", "dbschema_id": "my_schema" }

Get the resolved LLM authoring pipeline for a schema and instance:

{ "resource_type": "database_llm_authoring_pipeline", "resource_id": "my_schema", "dbinstance_id": "prod_db" }

List snapshot object names (e.g. tables) for a schema instance:

{
  "resource_type": "database_snapshot_object",
  "dbschema_id": "my_schema",
  "dbinstance_id": "prod_db",
  "object_type": "Table"
}

Get full snapshot metadata for specific named objects:

{
  "resource_type": "database_snapshot_object",
  "resource_id": "prod_db",
  "params": {
    "dbschema_id": "my_schema",
    "object_type": "Table",
    "object_names": ["users", "orders"]
  }
}

Pipeline Run Workflow (Recommended)

Use this sequence to reduce execution-time input errors:

1. Discover required runtime inputs

• harness_get(resource_type="runtime_input_template", resource_id="<pipeline_id>")
• The returned template shows <+input> placeholders that need values.

2. Choose input strategy

• Simple variables: pass flat key-value inputs (for example {"branch":"main","env":"prod"}).

• Complex/structural inputs: use input_set_ids (CI codebase/build blocks and nested template inputs are best handled this way).

• CI codebase shorthand keys (pipeline run only):

  Shorthand key	Expanded structure
  branch	build.type=branch, build.spec.branch=<value>
  tag	build.type=tag, build.spec.tag=<value>
  pr_number	build.type=PR, build.spec.number=<value>
  commit_sha	build.type=commitSha, build.spec.commitSha=<value>

• Constraint: shorthand expansion is skipped when inputs.build is already present (explicit build wins).

3. Execute the run

• harness_execute(resource_type="pipeline", action="run", resource_id="<pipeline_id>", ...)

• For Git-backed pipelines whose YAML should be loaded from a non-default branch, pass params.pipeline_branch (sent to Harness as pipelineBranchName):

  {
    "resource_type": "pipeline",
    "action": "run",
    "resource_id": "deploy_app",
    "params": { "pipeline_branch": "feature/new-stage" },
    "inputs": { "branch": "main" },
    "wait": true
  }
  

4. Optional: combine both

• Use input_set_ids for the base shape and inputs for simple overrides.

If required fields are unresolved, the tool returns a pre-flight error with expected keys and suggested input sets. You can inspect available shorthand mappings with harness_describe(resource_type="pipeline") (executeActions.run.inputShorthands).

Dynamic Pipeline Execution

Use pipeline_dynamic_execution.run when an agent or external system generates the full v0 pipeline YAML at runtime and needs to run it against an existing Harness pipeline shell. This is not a replacement for normal pipeline.run: the saved v0 pipeline must already exist, account-level and pipeline-level Allow Dynamic Execution must be enabled, and the caller needs Edit plus Execute permissions on the pipeline.

{
  "resource_type": "pipeline_dynamic_execution",
  "action": "run",
  "resource_id": "deploy_app",
  "body": {
    "yaml": "pipeline:\n  identifier: deploy_app\n  name: Deploy App\n  stages: []"
  },
  "params": {
    "module_type": "CD",
    "notes": "agent-generated dynamic run",
    "notify_only_user": true
  }
}

Constraints:

• body must be an object with a yaml field. Raw string bodies are rejected by the public harness_execute schema.
• body.yaml may be a YAML string or a JSON pipeline object; JSON is serialized to YAML before the request.
• Runtime <+input> placeholders are not resolved by this API. Submit fully resolved YAML.
• Input sets, selective stage execution, retry, and triggers are not supported by the dynamic execution endpoint.
• The action is high_write and uses the normal confirmation/auto-approval path. The response projects the API envelope to { "execution_id": "...", "status": "..." } and includes an openInHarness execution link when scope data is available.

If Harness rejects the run as not enabled, check both the account-level Allow Dynamic Execution setting and the pipeline-level toggle under Pipeline -> Advanced Options -> Dynamic Execution Settings.

Execution Input Forensics

Use execution_inputs after a run to inspect the merged input YAML that produced a specific execution. This is useful when a failure depends on input-set merging, Git-backed input set branches, or trigger/runtime values that are hard to reconstruct from the execution page alone.

{
  "resource_type": "execution_inputs",
  "resource_id": "PLAN_EXECUTION_ID",
  "params": {
    "resolve_expressions": true,
    "resolve_expressions_type": "RESOLVE_ALL_EXPRESSIONS"
  }
}

The get response is projected to:

• executionId - the plan execution ID from resource_id.
• inputSetYaml - merged runtime input YAML used for the run, or null.
• inputSetTemplateYaml - input template at execution time, or null.
• resolvedYaml - expression-resolved YAML when resolve_expressions=true, otherwise usually null.
• inputSetDetails - contributing saved input sets as { identifier, name } pairs.
• inputSetBranchName - source branch for Git-backed input sets, or null.

execution_inputs is get-only and read-risk. If resolve_expressions is omitted, the server omits the API query parameters and Harness uses its default UNKNOWN resolution mode.

Pipeline Execute Wait Mode

For pipeline.run, pipeline.retry, and pipeline_v1.run, pass wait: true to let the server poll until the execution reaches a terminal status. This keeps a pipeline launch and status check in one tool call instead of asking the client or LLM to run a polling loop.

{
  "resource_type": "pipeline",
  "action": "run",
  "resource_id": "deploy_app",
  "inputs": { "branch": "main" },
  "wait": true,
  "wait_timeout_seconds": 900,
  "wait_poll_interval_seconds": 5
}

Wait mode behavior:

• Default timeout is 600 seconds; allowed range is 10 seconds to 7200 seconds.
• Initial poll interval defaults to 3 seconds, backs off by 1.5x, and caps at 30 seconds.
• On success or failure, the response includes fields such as execution_id, execution_status, execution_terminal, execution_elapsed_ms, and execution_poll_count.
• If the timeout fires, the original trigger still succeeded; the response includes execution_timed_out: true and _wait.hint with the last observed status.
• If polling fails after the trigger succeeds, the response includes _wait.error and a recheck hint. Do not blindly rerun the pipeline unless you have confirmed the first execution is not running.
• Failed terminal statuses include _diagnose_hint pointing to harness_diagnose(resource_type="execution", options={execution_id: "..."}).

Ask the AI DevOps Agent to create a pipeline:

{
  "prompt": "Create a pipeline that builds a Go app with Docker and deploys to Kubernetes",
  "action": "CREATE_PIPELINE"
}

Update a service via natural language:

{
  "prompt": "Add a sidecar container for logging",
  "action": "UPDATE_SERVICE",
  "conversation_id": "prev-conversation-id",
  "context": [{ "type": "yaml", "payload": "<existing service YAML>" }]
}

Pipeline Storage Modes

Harness pipelines can be stored in three ways:

Mode	Description	When to use
Inline	Pipeline YAML stored in Harness	Default. Simplest setup, no Git required.
Remote (External Git)	Pipeline YAML stored in GitHub, GitLab, Bitbucket, etc.	Teams using Git-backed pipeline-as-code with an external provider.
Remote (Harness Code)	Pipeline YAML stored in a Harness Code repository	Teams using Harness's built-in Git hosting.

Create an inline pipeline (default):

// harness_create
{
  "resource_type": "pipeline",
  "body": {
    "yamlPipeline": "pipeline:\n  name: My Pipeline\n  identifier: my_pipeline\n  stages:\n    - stage:\n        name: Build\n        type: CI\n        spec:\n          execution:\n            steps:\n              - step:\n                  type: Run\n                  name: Echo\n                  spec:\n                    command: echo hello"
  }
}

Create a remote pipeline (External Git — e.g. GitHub):

// harness_create
{
  "resource_type": "pipeline",
  "body": {
    "yamlPipeline": "pipeline:\n  name: Deploy Service\n  identifier: deploy_service\n  stages: []"
  },
  "params": {
    "store_type": "REMOTE",
    "connector_ref": "my_github_connector",
    "repo_name": "my-repo",
    "branch": "main",
    "file_path": ".harness/deploy-service.yaml",
    "commit_msg": "Add deploy pipeline via MCP"
  }
}

Create a remote pipeline (Harness Code — no connector needed):

// harness_create
{
  "resource_type": "pipeline",
  "body": {
    "yamlPipeline": "pipeline:\n  name: Build App\n  identifier: build_app\n  stages: []"
  },
  "params": {
    "store_type": "REMOTE",
    "is_harness_code_repo": true,
    "repo_name": "product-management",
    "branch": "main",
    "file_path": ".harness/build-app.yaml",
    "commit_msg": "Add build pipeline via MCP"
  }
}

Update a remote pipeline:

// harness_update
{
  "resource_type": "pipeline",
  "resource_id": "deploy_service",
  "body": {
    "yamlPipeline": "pipeline:\n  name: Deploy Service\n  identifier: deploy_service\n  stages:\n    - stage:\n        name: Deploy\n        type: Deployment"
  },
  "params": {
    "store_type": "REMOTE",
    "connector_ref": "my_github_connector",
    "repo_name": "my-repo",
    "branch": "main",
    "file_path": ".harness/deploy-service.yaml",
    "commit_msg": "Update deploy pipeline via MCP",
    "last_object_id": "abc123",
    "last_commit_id": "def456"
  }
}

Import a pipeline from an external Git repo:

// harness_execute
{
  "resource_type": "pipeline",
  "action": "import",
  "params": {
    "connector_ref": "my_github_connector",
    "repo_name": "my-repo",
    "branch": "main",
    "file_path": ".harness/existing-pipeline.yaml"
  },
  "body": {
    "pipeline_name": "Existing Pipeline",
    "pipeline_description": "Imported from GitHub"
  }
}

Import a pipeline from a Harness Code repo:

// harness_execute
{
  "resource_type": "pipeline",
  "action": "import",
  "params": {
    "is_harness_code_repo": true,
    "repo_name": "product-management",
    "branch": "main",
    "file_path": ".harness/existing-pipeline.yaml"
  },
  "body": {
    "pipeline_name": "Existing Pipeline"
  }
}

Create a connector:

{
  "resource_type": "connector",
  "body": { "connector": { "name": "My Docker Hub", "identifier": "my_docker", "type": "DockerRegistry" } }
}

Delete a trigger:

{
  "resource_type": "trigger",
  "resource_id": "nightly-trigger",
  "pipeline_id": "my-pipeline"
}

List input sets for a pipeline:

{
  "resource_type": "input_set",
  "pipeline_id": "my-pipeline"
}

Get a specific input set:

{
  "resource_type": "input_set",
  "resource_id": "prod-inputs",
  "pipeline_id": "my-pipeline"
}

Create an input set:

{
  "resource_type": "input_set",
  "pipeline_id": "my-pipeline",
  "body": "inputSet:\n  name: Production Inputs\n  identifier: prod_inputs\n  pipeline:\n    identifier: my-pipeline\n    variables:\n      - name: env\n        type: String\n        value: production"
}

Update an input set:

{
  "resource_type": "input_set",
  "resource_id": "prod_inputs",
  "pipeline_id": "my-pipeline",
  "body": "inputSet:\n  name: Production Inputs\n  identifier: prod_inputs\n  pipeline:\n    identifier: my-pipeline\n    variables:\n      - name: env\n        type: String\n        value: production\n      - name: replicas\n        type: String\n        value: \"3\""
}

Delete an input set:

{
  "resource_type": "input_set",
  "resource_id": "prod_inputs",
  "pipeline_id": "my-pipeline"
}

Resource Types

218 resource types organized across 38 toolsets. Each resource type supports a subset of CRUD operations and optional execute actions.

Platform

Resource Type	List	Get	Create	Update	Delete	Execute Actions
organization	x	x	x	x	x
project	x	x	x	x	x

Pipelines

Resource Type	List	Get	Create	Update	Delete	Execute Actions
pipeline	x	x	x	x	x	run, retry
pipeline_v1 (Alpha)	x	x	x	x	x	run
pipeline_dynamic_execution						run
execution	x	x				interrupt
execution_inputs		x
trigger	x	x	x	x	x
pipeline_summary		x
input_set	x	x	x	x	x
runtime_input_template		x
approval_instance	x					approve, reject

Only one pipeline YAML resource type is loaded at startup. By default HARNESS_PIPELINE_VERSION=0 exposes pipeline and hides pipeline_v1; set HARNESS_PIPELINE_VERSION=1 to expose pipeline_v1 and hide pipeline. In HTTP mode, include x-harness-pipeline-version: 0 or 1 on the initialize request to choose the version for that session.

AI Agents

Resource Type	List	Get	Create	Update	Delete	Execute Actions
agent	x	x	x	x	x
agent_run	x

Services

Resource Type	List	Get	Create	Update	Delete	Execute Actions
service	x	x	x	x	x

Environments

Resource Type	List	Get	Create	Update	Delete	Execute Actions
environment	x	x	x	x	x	move_configs

Connectors

Resource Type	List	Get	Create	Update	Delete	Execute Actions
connector	x	x	x	x	x	test_connection
connector_catalogue	x

Infrastructure

Resource Type	List	Get	Create	Update	Delete	Execute Actions
infrastructure	x	x	x	x	x	move_configs

Secrets

Resource Type	List	Get	Create	Update	Delete	Execute Actions
secret	x	x

Execution Logs

Resource Type	List	Get	Create	Update	Delete	Execute Actions
execution_log		x

Audit Trail

Resource Type	List	Get	Create	Update	Delete	Execute Actions
audit_event	x	x

Delegates

Resource Type	List	Get	Create	Update	Delete	Execute Actions
delegate	x
delegate_token	x	x	x		x	revoke, get_delegates

Code Repositories

Resource Type	List	Get	Create	Update	Delete	Execute Actions
repository	x	x	x	x
branch	x	x	x		x
commit	x	x	x			diff, diff_stats
file_content		x				blame
tag	x		x		x
repo_rule	x	x
space_rule	x	x

commit creation commits one or more file actions directly through the Harness Code API without cloning. Pass body.title, body.branch, and body.actions; each action is CREATE, UPDATE, DELETE, or MOVE, and UPDATE requires the current blob SHA.

Artifact Registries

Resource Type	List	Get	Create	Update	Delete	Execute Actions
registry	x	x
artifact	x
artifact_version	x
artifact_file	x

File Store

Resource Type	List	Get	Create	Update	Delete	Execute Actions
file_store	x	x	x	x	x	list_children

file_store manages Harness File Store files and folders through the generic tools. It supports account, org, and project scope; pass resource_scope="account"|"org"|"project" or paste a Harness File Store URL so the server can derive scope and IDs.

Common calls:

# List the account-level File Store.
harness_list(resource_type="file_store", resource_scope="account")

# Create a folder at the current scope root.
harness_create(resource_type="file_store", body={
  name: "scripts",
  type: "FOLDER",
  parent_identifier: "Root"
})

# Upload a UTF-8 script file. Use content_base64 instead for binary data.
harness_create(resource_type="file_store", body={
  name: "deploy.sh",
  type: "FILE",
  parent_identifier: "Root",
  content: "#!/usr/bin/env bash\n./deploy",
  mime_type: "text/x-shellscript",
  file_usage: "SCRIPT"
})

# Rename metadata without replacing file content.
harness_update(resource_type="file_store", resource_id="deploy_script", body={
  name: "deploy-prod.sh",
  type: "FILE",
  parent_identifier: "Root"
})

# List first-level children of a folder. This is a read-risk execute action.
harness_execute(resource_type="file_store", action="list_children",
  resource_id="scripts_folder", params={folder_name: "scripts"})

Multipart body constraints:

• Create/update accept JSON body, then convert it to multipart/form-data for /ng/api/file-store.
• name, type (FILE or FOLDER), and parent_identifier are required; use the literal "Root" only for the root of the selected scope.
• FILE create requires exactly one of content (UTF-8 string) or content_base64 (valid non-empty base64). FILE update can omit content for metadata-only updates, or provide exactly one content field to replace content.
• FOLDER create/update must omit content and content_base64.
• Optional file_usage must be MANIFEST_FILE, CONFIG, or SCRIPT; optional scalar metadata such as description, mime_type, path, and tags must be strings.
• Upload content is capped at 100 MB. Confirmation prompts redact content, content_base64, and contentBase64 previews before elicitation.

list_children accepts either shorthand (resource_id plus params.folder_name, or params.file_store_id/params.folder_identifier plus params.folder_name) or a full FileStoreNode body with identifier, name, and type: "FOLDER". Full bodies use Harness camelCase parentIdentifier; shorthand may use params.parent_identifier.

Templates

Resource Type	List	Get	Create	Update	Delete	Execute Actions
template	x	x	x	x	x

Template operations use the Harness Template service paths (/template/api/templates...). Create and update require the full template YAML string in body.template_yaml or body.yaml; version_label targets a specific version for update/delete, while deleting without version_label deletes all versions.

Dashboards

Resource Type	List	Get	Create	Update	Delete	Execute Actions
dashboard	x	x
dashboard_data		x

Database DevOps

Resource Type	List	Get	Create	Update	Delete	Execute Actions
database_schema	x	x	x	x	x
database_instance	x	x	x	x	x
database_snapshot_object	x	x
database_llm_authoring_pipeline		x

Infrastructure as Code Management (IaCM)

IaCM resources are default-enabled and mostly project-scoped. Start with iacm_workspace to find workspace identifiers, then use that workspace_id for workspace resources, costs, and activity diffs. The module registry is account-scoped.

Resource Type	List	Get	Create	Update	Delete	Execute Actions
iacm_workspace	x	x
iacm_resource	x
iacm_module	x	x
iacm_workspace_costs	x
iacm_activity_resource_change	x

Typical workflow:

1. harness_list(resource_type="iacm_workspace", org_id="...", project_id="...") to find the workspace.
2. harness_list(resource_type="iacm_resource", org_id="...", project_id="...", workspace_id="...") to inspect Terraform resources, outputs, and data sources.
3. harness_list(resource_type="iacm_workspace_costs", org_id="...", project_id="...", workspace_id="...") to review per-execution cost entries.
4. harness_list(resource_type="iacm_activity_resource_change", org_id="...", project_id="...", activity_id="...", workspace_id="...") to inspect before/after resource diffs for a plan, apply, or destroy activity.

IaCM list responses expose page_count as the count for the current page only. When has_more is true, keep requesting the next 1-based page and sum page counts if you need a total.

Internal Developer Portal (IDP)

Resource Type	List	Get	Create	Update	Delete	Execute Actions
idp_entity	x	x
scorecard	x	x
scorecard_check	x	x
scorecard_stats		x
scorecard_check_stats		x
idp_score	x	x
idp_workflow	x					execute
idp_tech_doc	x

Pull Requests

Resource Type	List	Get	Create	Update	Delete	Execute Actions
pull_request	x	x	x	x		close, merge
pr_reviewer	x		x			submit_review
pr_comment	x		x
pr_check	x
pr_activity	x

Use harness_execute(resource_type="pull_request", action="close", ...) for an explicit close operation. harness_update also accepts body.state (open or closed) and routes state changes to the dedicated Harness Code PR state endpoint; send title/description edits in a separate update call.

Feature Flags

Resource Type	List	Get	Create	Update	Delete	Execute Actions
fme_workspace	x
fme_environment	x
fme_feature_flag	x	x	x	x	x	kill, restore, archive, unarchive
fme_feature_flag_definition		x	x	x
fme_rollout_status	x
fme_rule_based_segment	x	x	x		x
fme_rule_based_segment_definition	x			x		enable, disable, change_request
fme_traffic_type	x
fme_identity			x	x
fme_standard_segment	x	x
fme_segment_keys	x			x

FME (Split.io) resources — fme_* resources use the Split.io API (api.split.io) and are scoped by workspace ID rather than org/project. In single-user/self-hosted mode, auth uses a Bearer token from HARNESS_FME_API_KEY, falling back to a non-placeholder HARNESS_API_KEY. HARNESS_FME_API_KEY may be a legacy Split admin key or an FME-entitled Harness PAT/SAT, but it is rejected in multi-user mode so shared deployments cannot override each session user's credential. Hosted OAuth/service-routing credentials for Harness platform APIs do not authenticate direct Split.io requests. fme_feature_flag supports full lifecycle management: create (requires traffic_type_id), list, get, update metadata, delete, and kill/restore/archive/unarchive execute actions. Use fme_traffic_type to discover traffic type IDs, fme_identity to create/update identity attributes, and fme_standard_segment / fme_segment_keys to inspect standard segments and add member keys. fme_rule_based_segment provides CRUD for targeting segments, while fme_rule_based_segment_definition manages environment-specific segment rules with enable/disable and change request approval flows.

GitOps

Resource Type	List	Get	Create	Update	Delete	Execute Actions
gitops_agent	x	x
gitops_application	x	x				sync
gitops_cluster	x	x
gitops_repository	x	x
gitops_applicationset	x	x
gitops_repo_credential	x	x
gitops_app_event	x
gitops_pod_log		x
gitops_managed_resource	x
gitops_resource_action	x
gitops_dashboard		x
gitops_app_resource_tree		x

Chaos Engineering

Resource Type	List	Get	Create	Update	Delete	Execute Actions
chaos_experiment	x	x	x		x	run, stop
chaos_experiment_run		x
chaos_experiment_variable	x
chaos_component_variable		x
chaos_input_set	x	x	x	x	x
chaos_experiment_template	x	x			x	create_from_template
chaos_probe	x	x	x		x	enable, verify
chaos_probe_in_run	x
chaos_probe_template	x	x			x
chaos_infrastructure	x
chaos_k8s_infrastructure	x	x				check_health
chaos_environment	x
chaos_hub	x	x	x	x	x
chaos_hub_fault	x
chaos_fault	x	x			x
chaos_fault_template	x	x			x
chaos_fault_experiment_run	x
chaos_action	x	x			x
chaos_action_template	x	x			x
chaos_loadtest	x	x	x		x	run, stop
chaos_application_map	x	x
discovered_namespace	x
discovered_service	x
discovered_network_map	x
chaos_guard_condition	x	x			x
chaos_guard_rule	x	x			x	enable
chaos_recommendation	x	x
chaos_risk	x	x
chaos_dr_test	x		x

Cloud Cost Management (CCM)

Resource Type	List	Get	Create	Update	Delete	Execute Actions
cost_perspective	x	x	x	x	x
cost_breakdown	x
cost_timeseries	x
cost_summary	x	x
cost_recommendation	x	x				update_state, override_savings, create_jira_ticket, create_snow_ticket
cost_anomaly	x
cost_anomaly_summary		x
cost_category	x	x
cost_account_overview		x
cost_filter_value	x
cost_recommendation_stats		x
cost_recommendation_detail		x
cost_commitment		x

Software Engineering Insights (SEI)

SEI resources are consolidated for token efficiency. Use metric or aspect params for DORA, team/org-tree details, and AI insights.

Resource Type	List	Get	Create	Update	Delete	Execute Actions
sei_metric	x
sei_productivity_metric		x
sei_dora_metric		x				Pass metric: deployment_frequency, change_failure_rate, mttr, lead_time, or *_drilldown
sei_team	x	x
sei_team_detail	x					Pass aspect: integrations, developers, integration_filters
sei_org_tree	x	x
sei_org_tree_detail	x	x				Pass aspect: efficiency_profile, productivity_profile, business_alignment_profile, integrations, teams
sei_business_alignment	x	x				Pass aspect: feature_metrics, feature_summary, drilldown for get
sei_ai_usage	x	x				Pass aspect: metrics, breakdown, summary, top_languages
sei_ai_adoption	x	x				Pass aspect: metrics, breakdown, summary
sei_ai_impact		x				Pass aspect: pr_velocity, rework
sei_ai_raw_metric	x

Software Supply Chain Assurance (SCS)

Resource Type	List	Get	Create	Update	Delete	Execute Actions
scs_artifact_source	x
artifact_security	x	x
scs_artifact_component	x
scs_artifact_remediation		x
scs_chain_of_custody		x
scs_compliance_result	x
code_repo_security	x	x
scs_sbom		x

Security Testing Orchestration (STO)

Resource Type	List	Get	Create	Update	Delete	Execute Actions
security_issue	x
security_issue_filter	x
security_exemption	x		x			approve, reject

security_exemption create is a high_write operation. The server derives requester_id from the authenticated PAT, sets exemptFutureOccurrences=true, and defaults duration_days to 30 when not provided. For listing exemptions, pass a small explicit page size (for example filters: { "status": "Pending", "size": 5 }) and follow the _nextPageHint returned in each response.

Security exemption execute workflow:

• Use harness_list with resource_type="security_exemption" and an explicit status such as Pending, Approved, Rejected, Expired, or Canceled.
• Use harness_execute with action="approve" and a required body.scope: CURRENT, ACCOUNT, ORG, or PROJECT. CURRENT approves at the exemption's existing scope; the other scopes use the STO promote endpoint internally. The server auto-fills body.approver_id from the authenticated user when omitted; body.comment is optional.
• Use action="reject" to reject an exemption. body.approver_id is also auto-filled when omitted.
• There is no separate promote execute action. Use action="approve" with a non-CURRENT body.scope when the requested outcome is approval at account, organization, or project scope.

Access Control

Resource Type	List	Get	Create	Update	Delete	Execute Actions
user	x	x
user_group	x	x	x		x
service_account	x	x	x		x
role	x	x	x		x
role_assignment	x		x
resource_group	x	x	x		x
permission	x

Governance

Resource Type	List	Get	Create	Update	Delete	Execute Actions
policy	x	x	x	x	x
policy_set	x	x	x	x	x
policy_evaluation	x	x

Deployment Freeze

Resource Type	List	Get	Create	Update	Delete	Execute Actions
freeze_window	x	x	x	x	x	toggle_status
global_freeze		x				manage

Service Overrides

Resource Type	List	Get	Create	Update	Delete	Execute Actions
service_override	x	x	x	x	x

Settings

Resource Type	List	Get	Create	Update	Delete	Execute Actions
setting	x

Visualizations

Inline PNG chart visualizations rendered from Harness data. These are metadata-only resource types with no API operations — they exist so the LLM can discover available chart types via harness_describe. Use include_visual=true on supported tools (harness_diagnose, harness_list, harness_status) to generate charts.

Resource Type	Description	How to Generate
visual_timeline	Gantt chart of pipeline stage execution over time	harness_diagnose with visual_type: "timeline"
visual_stage_flow	DAG flowchart of pipeline stages and steps	harness_diagnose with visual_type: "flow"
visual_health_dashboard	Project health overview with status indicators	harness_status with include_visual: true
visual_pie_chart	Donut chart of execution status breakdown	harness_list with visual_type: "pie"
visual_bar_chart	Bar chart of execution counts by pipeline	harness_list with visual_type: "bar"
visual_timeseries	Daily execution trend over 30 days	harness_list with visual_type: "timeseries"
visual_architecture	Pipeline YAML architecture diagram (stages → steps)	harness_diagnose with visual_type: "architecture"

MCP Prompts

DevOps

Prompt	Description	Parameters
build-deploy-app	End-to-end CI/CD workflow: scan a git repo, generate CI pipeline (build & push Docker image), discover or generate K8s manifests, create CD pipeline, and deploy — with auto-retry on CI failures (up to 5 attempts) and CD failures (up to 3 attempts with user permission). On exhausted retries, provides Harness UI deep links to all created resources for manual investigation.	repoUrl (required), imageName (required), projectId (optional), namespace (optional)
debug-pipeline-failure	Analyze a failed execution: accepts an execution ID, pipeline ID, or Harness URL. Gets stage/step breakdown, failure details, delegate info, and failed step logs via harness_diagnose, then provides root cause analysis and suggested fixes. Automatically follows chained pipeline failures.	executionId (optional), projectId (optional)
create-pipeline	Generate a new pipeline YAML from natural language requirements, reviewing existing resources for context	description (required), projectId (optional)
create-agent	Interactively build a Harness AI agent — check existing agents, gather requirements, generate agent YAML spec using the agent-pipeline schema, confirm with user, then create or update via harness_create/harness_update	agent_name (required), task_description (required), org_id (optional), project_id (optional)
onboard-service	Walk through onboarding a new service with environments and a deployment pipeline	serviceName (required), projectId (optional)
dora-metrics-review	Review DORA metrics (deployment frequency, change failure rate, MTTR, lead time) with Elite/High/Medium/Low classification and improvement recommendations	teamRefId (optional), dateStart (optional), dateEnd (optional)
setup-gitops-application	Guide through onboarding a GitOps application — verify agent, cluster, repo, and create the application	agentId (required), projectId (optional)
chaos-resilience-test	Design a chaos experiment to test service resilience with fault injection, probes, and expected outcomes	serviceName (required), projectId (optional)
feature-flag-rollout	Plan and execute a progressive feature flag rollout across environments with safety gates	flagIdentifier (required), projectId (optional)
migrate-pipeline-to-template	Analyze an existing pipeline and extract reusable stage/step templates from it	pipelineId (required), projectId (optional)
delegate-health-check	Check delegate connectivity, health, token status, and troubleshoot infrastructure issues	projectId (optional)
developer-portal-scorecard	Review IDP scorecards for services and identify gaps to improve developer experience	projectId (optional)
pending-approvals	Find pipeline executions waiting for approval, show details, and offer to approve or reject	projectId (optional), orgId (optional), pipelineId (optional)

FinOps

Prompt	Description	Parameters
optimize-costs	Analyze cloud cost data, surface recommendations and anomalies, prioritized by potential savings	projectId (optional)
cloud-cost-breakdown	Deep-dive into cloud costs by service, environment, or cluster with trend analysis and anomaly detection	perspectiveId (optional), projectId (optional)
commitment-utilization-review	Analyze reserved instance and savings plan utilization to find waste and optimize commitments	projectId (optional)
cost-anomaly-investigation	Investigate cost anomalies — determine root cause, impacted resources, and remediation	projectId (optional)
rightsizing-recommendations	Review and prioritize rightsizing recommendations, optionally create Jira or ServiceNow tickets	projectId (optional), minSavings (optional)

DevSecOps

Prompt	Description	Parameters
security-review	Review security issues across Harness resources and suggest remediations by severity	projectId (optional), severity (optional, default: critical,high)
vulnerability-triage	Triage security vulnerabilities across pipelines and artifacts, prioritize by severity and exploitability	projectId (optional), severity (optional)
sbom-compliance-check	Audit SBOM and compliance posture for artifacts — license risks, policy violations, component vulnerabilities	artifactId (optional), projectId (optional)
supply-chain-audit	End-to-end software supply chain security audit — provenance, chain of custody, policy compliance	projectId (optional)
security-exemption-review	Review pending security exemptions and make batch approval or rejection decisions	projectId (optional)
bulk-exemption-create	Create justified security exemptions for multiple STO issues with explicit scope and duration guidance	projectId (required), exemption_type (required), reason (required), issue filters (optional)
access-control-audit	Audit user permissions, over-privileged accounts, and role assignments to enforce least-privilege	projectId (optional), orgId (optional)

Harness Code

Prompt	Description	Parameters
code-review	Review a pull request — analyze diff, commits, checks, and comments to provide structured feedback on bugs, security, performance, and style	repoId (required), prNumber (required), projectId (optional)
pr-summary	Auto-generate a PR title and description from the commit history and diff of a branch	repoId (required), sourceBranch (required), targetBranch (optional, default: main), projectId (optional)
branch-cleanup	Analyze branches in a repository and recommend stale or merged branches to delete	repoId (required), projectId (optional)

MCP Resources

Resource URI	Description	MIME Type
pipeline:///{pipelineId}	Pipeline YAML definition	application/x-yaml
pipeline:///{orgId}/{projectId}/{pipelineId}	Pipeline YAML (with explicit scope)	application/x-yaml
executions:///recent	Last 10 pipeline execution summaries	application/json
schema:///pipeline	Harness pipeline JSON Schema	application/schema+json
schema:///template	Harness template JSON Schema	application/schema+json
schema:///trigger	Harness trigger JSON Schema	application/schema+json
schema:///pipeline_v1 (Alpha)	Harness V1 pipeline JSON Schema (simplified stages/steps format)	application/schema+json
schema:///agent-pipeline	Harness AI agent pipeline JSON Schema	application/schema+json

Toolset Filtering

By default, 38 of 39 toolsets are enabled. One toolset is opt-in and excluded from the defaults:

• ansible — Harness Ansible (inventories, playbooks, hosts, activity). Opt-in because it is project-scoped and adds concepts many users do not need.

Adding toolsets with + prefix

Use the + prefix to explicitly include opt-in toolsets alongside all defaults:

# Explicitly include Ansible alongside all defaults
HARNESS_TOOLSETS=+ansible

Removing default toolsets

Use the - prefix to exclude toolsets you don't need:

# Remove chaos and ccm from defaults
HARNESS_TOOLSETS=-chaos,-ccm

Combining + and -

# Add Ansible, remove chaos
HARNESS_TOOLSETS=+ansible,-chaos

Explicit allowlist

An explicit comma-separated list (no prefixes) replaces the defaults entirely. Only the listed toolsets are enabled:

# Only expose pipelines, services, and connectors
HARNESS_TOOLSETS=pipelines,services,connectors

Available toolset names:

Toolset	Resource Types
platform	organization, project
pipelines	pipeline, pipeline_v1, pipeline_dynamic_execution, execution, execution_inputs, trigger, pipeline_summary, input_set, approval_instance
agents	agent, agent_run
services	service
environments	environment
connectors	connector, connector_catalogue
infrastructure	infrastructure
secrets	secret
logs	execution_log
audit	audit_event
delegates	delegate, delegate_token
repositories	repository, branch, commit, file_content, tag, repo_rule, space_rule
registries	registry, artifact, artifact_version, artifact_file
file_store	file_store
templates	template
dashboards	dashboard, dashboard_data
idp	idp_entity, scorecard, scorecard_check, scorecard_stats, scorecard_check_stats, idp_score, idp_workflow, idp_tech_doc
pull-requests	pull_request, pr_reviewer, pr_comment, pr_check, pr_activity
feature-flags	fme_workspace, fme_environment, fme_feature_flag, fme_feature_flag_definition, fme_rollout_status, fme_rule_based_segment, fme_rule_based_segment_definition, fme_traffic_type, fme_identity, fme_standard_segment, fme_segment_keys
gitops	gitops_agent, gitops_application, gitops_cluster, gitops_repository, gitops_applicationset, gitops_repo_credential, gitops_app_event, gitops_pod_log, gitops_managed_resource, gitops_resource_action, gitops_dashboard, gitops_app_resource_tree
chaos	chaos_experiment, chaos_experiment_run, chaos_experiment_variable, chaos_component_variable, chaos_input_set, chaos_experiment_template, chaos_probe, chaos_probe_in_run, chaos_probe_template, chaos_infrastructure, chaos_k8s_infrastructure, chaos_environment, chaos_hub, chaos_hub_fault, chaos_fault, chaos_fault_template, chaos_fault_experiment_run, chaos_action, chaos_action_template, chaos_loadtest, chaos_application_map, discovered_namespace, discovered_service, discovered_network_map, chaos_guard_condition, chaos_guard_rule, chaos_recommendation, chaos_risk, chaos_dr_test
ccm	cost_perspective, cost_breakdown, cost_timeseries, cost_summary, cost_recommendation, cost_anomaly, cost_anomaly_summary, cost_category, cost_account_overview, cost_filter_value, cost_recommendation_stats, cost_recommendation_detail, cost_commitment
sei	sei_metric, sei_productivity_metric, sei_dora_metric, sei_team, sei_team_detail, sei_org_tree, sei_org_tree_detail, sei_business_alignment, sei_ai_usage, sei_ai_adoption, sei_ai_impact, sei_ai_raw_metric
scs	scs_artifact_source, artifact_security, scs_artifact_component, scs_artifact_remediation, scs_chain_of_custody, scs_compliance_result, code_repo_security, scs_sbom
sto	security_issue, security_issue_filter, security_exemption
dbops	database_schema, database_instance, database_snapshot_object, database_llm_authoring_pipeline
access_control	user, user_group, service_account, role, role_assignment, resource_group, permission
governance	policy, policy_set, policy_evaluation
freeze	freeze_window, global_freeze
overrides	service_override
settings	setting
visualizations	visual_timeline, visual_stage_flow, visual_health_dashboard, visual_pie_chart, visual_bar_chart, visual_timeseries, visual_architecture
knowledge-graph	kg_queryable_type_summary, kg_grammar, hql_query
semantic-layer	kg_type, kg_related_type
ai-evals	eval_dataset, eval_dataset_item, evaluation, eval_run, eval_run_item, eval_run_by_eval, eval_metric, eval_metric_set, eval_metric_set_entry, eval_suite, eval_suite_evaluation, eval_suite_run, eval_target, eval_annotation, eval_analytics, eval_git_settings, eval_registry_item, eval_git_registration, online_eval
iacm	iacm_workspace, iacm_resource, iacm_module, iacm_workspace_costs, iacm_activity_resource_change
ansible (opt-in)	ansible_inventory, ansible_playbook, ansible_host, ansible_host_activity, ansible_activity

Architecture

                 +------------------+
                 |   AI Agent       |
                 |  (Claude, etc.)  |
                 +--------+---------+
                          |  MCP (stdio or HTTP)
                 +--------v---------+
                |    MCP Server     |
                | 11 Generic Tools  |
                 +--------+---------+
                          |
                 +--------v---------+
                |    Registry       |  <-- Declarative resource definitions
                |  38 Toolsets      |      (data files, not code)
                |  218 Resource Types|
                 +--------+---------+
                          |
                 +--------v---------+
                 |  HarnessClient    |  <-- Auth, retry, rate limiting
                 +--------+---------+
                          |  HTTPS
                 +--------v---------+
                 |  Harness REST API |
                 +-------------------+

How It Works

1. Tools are generic verbs: harness_list, harness_get, etc. They accept a resource_type parameter that routes to the correct API endpoint.
2. The Registry maps each resource_type to a ResourceDefinition — a declarative data structure specifying the HTTP method, URL path, path/query parameter mappings, and response extraction logic.
3. Dispatch resolves the resource definition, builds the HTTP request (path substitution, query params, resource_scope-aware account/org/project injection), calls the Harness API through HarnessClient, and extracts the relevant response data.
4. Toolset filtering (HARNESS_TOOLSETS) controls which resource definitions are loaded into the registry at startup.
5. Structured output is declared with MCP outputSchema; harness_list coerces arrays and common list wrappers into object-shaped structuredContent for strict clients.
6. Deep links are automatically appended to responses, providing direct Harness UI URLs for every resource.
7. Compact mode strips verbose metadata from list results, keeping only actionable fields (identity, status, type, timestamps, deep links) to minimize token usage.

Adding a New Resource Type

Create a new file in src/registry/toolsets/ or add a resource to an existing toolset:

// src/registry/toolsets/my-module.ts
import type { ToolsetDefinition } from "../types.js";

export const myModuleToolset: ToolsetDefinition = {
  name: "my-module",
  displayName: "My Module",
  description: "Description of the module",
  resources: [
    {
      resourceType: "my_resource",
      displayName: "My Resource",
      description: "What this resource represents",
      toolset: "my-module",
      scope: "project",                    // "project" | "org" | "account"
      identifierFields: ["resource_id"],
      listFilterFields: ["search_term"],
      operations: {
        list: {
          method: "GET",
          path: "/my-module/api/resources",
          queryParams: { search_term: "search", page: "page", size: "size" },
          responseExtractor: (raw) => raw,
          description: "List resources",
        },
        get: {
          method: "GET",
          path: "/my-module/api/resources/{resourceId}",
          pathParams: { resource_id: "resourceId" },
          responseExtractor: (raw) => raw,
          description: "Get resource details",
        },
      },
    },
  ],
};

Then import it in src/registry/index.ts and add it to the ALL_TOOLSETS array. No changes needed to any tool files.

Development

# Build
pnpm build

# Watch mode
pnpm dev

# Type check
pnpm typecheck

# Run tests
pnpm test

# Watch tests
pnpm test:watch

# Interactive MCP Inspector
pnpm inspect

# Refresh generated README counts from the built registry
pnpm docs:generate

# Verify README counts and clone instructions are current
pnpm docs:check

# Sync and verify JSON Schemas used by harness_schema
pnpm sync-schemas
pnpm check-schema-coverage

Project Structure

src/
  index.ts                          # Entrypoint, transport setup
  config.ts                         # Env var validation (Zod)
  client/
    harness-client.ts               # HTTP client (auth, retry, rate limiting)
    types.ts                        # Shared API types
  registry/
    index.ts                        # Registry class + dispatch logic
    types.ts                        # ResourceDefinition, ToolsetDefinition, etc.
    toolsets/                        # One file per toolset (declarative data)
      platform.ts
      pipelines.ts
      services.ts
      ccm.ts
      access-control.ts
      ...
  tools/                            # 11 generic MCP tools
    harness-list.ts
    harness-get.ts
    harness-create.ts
    harness-update.ts
    harness-delete.ts
    harness-execute.ts
    harness-search.ts
    harness-diagnose.ts
    harness-describe.ts
    harness-status.ts
    harness-schema.ts

  resources/                        # MCP resource providers
    pipeline-yaml.ts
    execution-summary.ts
  prompts/                          # MCP prompt templates
    build-deploy-app.ts             # DevOps: end-to-end build & deploy workflow
    debug-pipeline.ts               # DevOps: debug failed executions
    create-pipeline.ts              # DevOps: generate pipeline from requirements
    onboard-service.ts              # DevOps: onboard new service
    dora-metrics.ts                 # DevOps: DORA metrics review
    setup-gitops.ts                 # DevOps: GitOps application setup
    chaos-resilience.ts             # DevOps: chaos experiment design
    feature-flag-rollout.ts         # DevOps: progressive flag rollout
    migrate-to-template.ts          # DevOps: extract templates from pipeline
    delegate-health.ts              # DevOps: delegate health check
    developer-scorecard.ts          # DevOps: IDP scorecard review
    optimize-costs.ts               # FinOps: cost optimization
    cloud-cost-breakdown.ts         # FinOps: cost deep-dive
    commitment-utilization.ts       # FinOps: RI/savings plan analysis
    cost-anomaly.ts                 # FinOps: anomaly investigation
    rightsizing.ts                  # FinOps: rightsizing recommendations
    security-review.ts              # DevSecOps: security issue review
    vulnerability-triage.ts         # DevSecOps: vulnerability triage
    sbom-compliance.ts              # DevSecOps: SBOM compliance audit
    supply-chain-audit.ts           # DevSecOps: supply chain audit
    exemption-review.ts             # DevSecOps: exemption approval
    access-control-audit.ts         # DevSecOps: access control audit
    code-review.ts                  # Harness Code: PR code review
    pr-summary.ts                   # Harness Code: auto-generate PR summary
    branch-cleanup.ts               # Harness Code: stale branch cleanup
    pending-approvals.ts            # Approvals: find and act on pending approvals
  utils/
    cli.ts                          # CLI arg parsing (transport, port)
    errors.ts                       # Error normalization
    logger.ts                       # stderr-only logger
    progress.ts                     # MCP progress & logging notifications
    rate-limiter.ts                 # Client-side rate limiting
    deep-links.ts                   # Harness UI deep link builder
    response-formatter.ts           # Consistent MCP response formatting
    compact.ts                      # Compact list output for token efficiency
tests/
  config.test.ts                    # Config schema validation tests
  utils/
    response-formatter.test.ts
    deep-links.test.ts
    errors.test.ts
  registry/
    registry.test.ts                # Registry loading, filtering, dispatch tests

Elicitation

The write tools (harness_create, harness_update, harness_delete, harness_execute) use MCP elicitation to prompt the user for confirmation when the action's risk requires it — medium_write, high_write, and destructive operations only. Low-risk creates / updates / reads (e.g. pipeline.create, pipeline.update, hql_query.run) proceed silently with no prompt. When a prompt is surfaced, the user sees what's about to happen and accepts or declines, giving real human-in-the-loop approval for the operations that actually mutate or run things.

How it works:

1. The LLM calls a write tool with medium_write+ risk (e.g. harness_delete, harness_execute pipeline.run). Low-risk creates / updates / reads do not surface a prompt.
2. The server sends an elicitation request to the client with a summary of the operation and a confirm checkbox (default checked).
3. The user sees the details and clicks Accept (with confirm checked) or Decline / Cancel.
4. If accepted with confirm: true, the operation proceeds. If accepted with confirm unchecked, declined, or cancelled, it's blocked and the LLM is told (an explicit decline is authoritative and not bypassed by confirm: true on the tool call).

Client support:

Client	Elicitation Support
Cursor	Yes
VS Code (Copilot)	Yes
Claude Desktop	Not yet
Devin Desktop	Not yet
MCP Inspector	Yes

Elicitation behavior varies by operation risk when client support is missing:

Risk Level	Client supports elicitation	confirm: true passed	Behavior
read, low_write	any	any	Proceed silently — no prompt is surfaced (confirm has no effect at this risk tier)
medium_write, high_write, destructive	Yes	any	Prompt user. Proceed only if user accepts with confirm: true (the schema's default). An explicit decline, cancel, or accept with confirm: false (user unchecked the box) is authoritative and is not bypassed by confirm: true on the tool call. An accept missing the confirm field is treated as the client failing to surface a usable prompt — recoverable by retrying with confirm: true
medium_write, high_write, destructive	No	No	BLOCK (return error with hint to retry with confirm: true)
medium_write, high_write, destructive	No	Yes	Proceed (explicit opt-in for non-interactive automation)
any (at or below HARNESS_AUTO_APPROVE_RISK)	any	any	Auto-approve without prompting

If elicitInput fails at runtime (transport error, unsupported method) for a medium_write+ operation, the call is blocked unless the caller passes confirm: true. confirm: true is honored as a fallback when the client could not surface a prompt or returned a degenerate accept ({action: "accept"} without the confirm field), but it does not override an explicit decline/cancel from a client that completed the elicitation handshake.

Autonomous Mode

Autonomous mode means the server proceeds with all operations — including writes and destructive actions — without prompting for confirmation. Enable it by setting:

HARNESS_AUTO_APPROVE_RISK=all

This is the deployment-level ceiling: once set, individual sessions cannot escalate beyond it (though they can choose a stricter threshold per-session via the x-harness-auto-approve-risk header).

Or in your MCP client config:

{
  "mcpServers": {
    "harness": {
      "command": "npx",
      "args": ["harness-mcp-v2"],
      "env": {
        "HARNESS_API_KEY": "pat.xxx.xxx.xxx",
        "HARNESS_AUTO_APPROVE_RISK": "all"
      }
    }
  }
}

Partial autonomy: You can also auto-approve only up to a specific risk level while still prompting for higher-risk operations:

# Auto-approve reads and low-risk writes; prompt for medium_write, high_write, destructive
HARNESS_AUTO_APPROVE_RISK=low_write

# Auto-approve up to high-risk writes; only prompt for destructive operations
HARNESS_AUTO_APPROVE_RISK=high_write

Value	What's auto-approved
none (default)	Nothing — no auto-approval threshold
low_write	Reads + low-risk writes
medium_write	Reads + low + medium-risk writes
high_write	Reads + low + medium + high-risk writes
all	Everything, including destructive operations

Autonomous mode warning: HARNESS_AUTO_APPROVE_RISK=all skips confirmation for all operations including harness_delete. Use with caution and consider pairing with HARNESS_TOOLSETS to restrict which resource types are available.

Migration note: HARNESS_SKIP_ELICITATION=true is still supported and maps to HARNESS_AUTO_APPROVE_RISK=all. A deprecation warning is logged to stderr. If both are set, HARNESS_AUTO_APPROVE_RISK takes precedence.

Safety

• Secrets are never exposed. The secret resource type returns metadata only (name, type, scope) — secret values are never included in any response.
• Confirmation-requiring operations use elicitation when available. When a write or execute action has medium_write, high_write, or destructive risk, harness_create, harness_update, harness_delete, and harness_execute attempt MCP elicitation before proceeding (see Elicitation). Low-risk actions (read, low_write — e.g. pipeline.create, pipeline.update, hql_query.run) proceed silently with no prompt.
• Medium-risk and above fail closed. If confirmation cannot be obtained for medium_write, high_write, or destructive operations, they are blocked instead of executing blindly. Override with HARNESS_AUTO_APPROVE_RISK for autonomous workflows.
• CORS restricted to same-origin. The HTTP transport only allows same-origin requests, preventing CSRF attacks from malicious websites targeting the MCP server on localhost.
• HTTP rate limiting. The HTTP transport enforces 60 requests per minute per IP to prevent request flooding.
• API rate limiting. The Harness API client enforces a 10 requests/second limit to avoid hitting upstream rate limits.
• Pagination bounds enforced. List queries are capped at 10,000 items total and 100 per page to prevent memory exhaustion.
• Retries with backoff. Transient failures (HTTP 429, 5xx) are retried with exponential backoff and jitter.
• Localhost binding. The HTTP transport binds to 127.0.0.1 by default — not accessible from the network.
• No stdout logging. All logs go to stderr to avoid corrupting the stdio JSON-RPC transport.

Complementary Skills

The Harness MCP server pairs well with Harness Skills — a collection of ready-made Claude Code skills (slash commands) designed for common Harness workflows. Install them alongside this MCP server to get high-level automation like /deploy, /rollback, /triage, and more without writing custom prompts.

Troubleshooting & Common Pitfalls

Symptom	Likely Cause	What to Do
HARNESS_ACCOUNT_ID is required when the API key does not include an account ID segment...	API key is not in a supported account-scoped format (pat.<accountId>... or sat.<accountId>...) so account ID cannot be inferred	Set HARNESS_ACCOUNT_ID explicitly
Unknown transport: "..." on startup	Unsupported CLI transport arg	Use stdio or http only
Invalid HARNESS_TOOLSETS: ... on startup	One or more toolset names are not recognized	Use only names from Toolset Filtering (exact match)
HTTP mcp-session-id header is required...	A session request was sent without session header	Send initialize first, then include mcp-session-id on POST/GET/DELETE /mcp
HTTP Session not found...	Session expired (30 min idle TTL) or already closed	Re-run initialize to create a new session, then retry with new header
HTTP 405 Method Not Allowed on /mcp	Unsupported method for MCP endpoint	Use POST, GET, DELETE, or OPTIONS only
HTTP Invalid request	Invalid JSON body or request body exceeded HARNESS_MAX_BODY_SIZE_MB	Validate JSON payload size/shape; increase HARNESS_MAX_BODY_SIZE_MB if needed
Unknown resource_type "..." from tools	Resource type is misspelled or filtered out via HARNESS_TOOLSETS	Call harness_describe (with optional search_term) to discover valid types
Missing required field "... for path parameter ..."	A project/org scoped call is missing identifiers	Set HARNESS_ORG/HARNESS_PROJECT or pass org_id/project_id per tool call
resource_scope "org" requires org_id... or resource_scope "project" requires project_id...	A multi-scope resource was forced to org/project scope without enough identifiers	Pass the missing org_id/project_id, configure HARNESS_ORG/HARNESS_PROJECT, or use resource_scope: "account" when supported
Read-only mode is enabled ... operations are not allowed	HARNESS_READ_ONLY=true blocks create/update/delete/execute	Set HARNESS_READ_ONLY=false if write operations are intended
Pipeline run fails pre-flight with unresolved required inputs	Provided inputs did not cover required runtime placeholders	Fetch runtime_input_template, supply missing simple keys, or use input_set_ids for structural inputs
Pipeline CI shorthand (branch, tag, pr_number, commit_sha) did not apply	inputs.build was already provided, so shorthand expansion was intentionally skipped	Remove inputs.build to use shorthand expansion, or keep full explicit build structure
Pipeline run loaded the wrong YAML revision	The pipeline definition is stored in Git and the run did not specify the desired pipeline branch	Pass params.pipeline_branch on the run action; this maps to Harness pipelineBranchName
wait: true returned _wait.error	The pipeline trigger succeeded, but server-side polling failed	Recheck the execution_id with harness_get(resource_type="execution", ...) before deciding whether to rerun
wait: true returned execution_timed_out: true	The execution did not reach a terminal status before wait_timeout_seconds	Use the returned execution_id to recheck status or diagnose the still-running execution
Execution logs are empty or blob downloads return 403	Harness-hosted log blob URLs require the configured Harness client/auth path, especially for internal or self-managed hosts	Keep HARNESS_BASE_URL pointed at the target Harness host and use harness_get(resource_type="execution_log", ...) or harness_diagnose(..., include_logs=true) rather than bypassing the MCP client
Operation declined by user / Operation cancelled by user	User declined or cancelled the elicitation confirmation dialog — authoritative	Verify operation details with the user; confirm: true does not bypass an explicit decline. The user must accept the prompt
Operation blocked: the client could not surface a usable confirmation prompt	Client lacks elicitation support, elicitInput failed, or returned a degenerate accept	Retry with confirm: true for non-interactive automation, or use a client that supports elicitation
body.template_yaml (or body.yaml) is required for template create/update	Template APIs expect full YAML payload	Provide full template_yaml string in body; for deletes, pass version_label to delete one version (omit to delete all versions)
HARNESS_BASE_URL must use HTTPS on startup	HARNESS_BASE_URL is set to an HTTP URL	Use HTTPS, or set HARNESS_ALLOW_HTTP=true for local development

License

MIT