gograph

Give Go coding agents a compiler-aware map for safer refactors.

gograph builds a local structural graph of your Go repository, with optional type-checked CHA/SSA enrichment. Its CLI and MCP workflows help coding agents trace callers and interface implementations, plan change impact, and enforce architecture without embeddings or a hosted code index.

Explore the interactive no-install demo · Review the reproducible benchmark

Companion projects: Scrinium provides repository-owned, evidence-backed knowledge for coding agents, while Rulefloor protects repository-local invariants by binding them to concrete tests and detecting drift. They are independent, optional tools: Scrinium can keep Gograph structural observations and Rulefloor validation results as separate evidence without treating either as proof of unrelated behavior or global project correctness.

Static analysis; no target-code execution. Default indexing parses Go source locally and does not call application services. Descendant links and special files for extensions recognized by go/build are excluded, graph-directed source reads are confined to regular files beneath the analyzed repository, and linked/non-regular Go tool metadata (go.mod, go.sum, go.work, go.work.sum, and vendor/modules.txt) is rejected before toolchain invocation; an explicitly symlinked repository root remains supported. Applicable go.work use members must stay beneath the workspace directory, and each member directory, go.mod, and optional go.sum is validated before cmd/go starts. Gograph also reads project metadata such as .gitignore, graph/config JSON, and Git state. Indexing asks the installed Go toolchain for the effective build/module context; precise mode additionally performs package type loading, and doc runs go doc. Those operations follow your configured module/cache/network policy. Before repository package loading or go doc, applicable local module/workspace source trees are preflighted for links that cmd/go may inspect; .git and .gograph subtrees are excluded. Session telemetry is local under .gograph/sessions/; nothing is sent to gograph services.

Quick Start

# Install
brew install --cask ozgurcd/tap/gograph
# or: go install github.com/ozgurcd/gograph/cmd/gograph@latest

# Confirm which installation will run and detect PATH shadowing
gograph doctor --json

# Build a type-enriched precise graph, then verify it
gograph build . --precise
gograph stats

# Optional: prioritize lower heap use on constrained hosts
gograph build . --precise --memory-mode=low --max-memory=1GiB

# Start with repository-wide results that require no guessed symbol
gograph summary
gograph hotspot --top 5
gograph flow --no-tests

Homebrew and go install install the normal gograph CLI. MCP clients that support MCP Bundles can instead discover the local stdio server in the official MCP Registry as io.github.ozgurcd/gograph. Registry/MCPB installation is a separate distribution path; it does not install the Homebrew cask or configure the Claude Code marketplace plugin. The Registry is currently in preview. See Official MCP Registry and MCPB installation for client support, target selection, and current limitations.

Choose a real function or method shown by summary, hotspot, or gograph complexity, then substitute its name below:

gograph context "YourSymbol" # source + callers + callees + tests

# For compilable repositories, enrich the graph before a major refactor
gograph build . --precise
gograph plan "YourSymbol"

Build artifacts are written under the target .gograph/ directory. gograph adds .gograph/ to the enclosing Git repository root .gitignore when available, falls back to the build target .gitignore outside Git, and exits without replacing artifacts if no Go files are found or no source file parses successfully. The update accepts only an absent or regular .gitignore; a repository-provided link is refused and its target is not modified. Go build constraints, cmd/go package-directory rules, generated sources, module-mode ignore directives, and Git ignores use the same scanner policy for building, freshness checks, and change detection. Source-file symlinks and other non-regular .go entries are reported and excluded; linked/non-regular go.mod, go.sum, go.work, go.work.sum, and vendor/modules.txt entries are rejected before gograph or the Go toolchain reads them. Applicable go.work use members must remain beneath the workspace directory; their directories, go.mod, and optional go.sum are validated before cmd/go starts. .gograph itself must be a real directory, and graph.json must be a regular repository-confined file. Graphs with a missing or unsupported confinement policy marker must be rebuilt with the current binary before graph-backed commands use them. Older binaries do not enforce this boundary and should not be used to analyze untrusted repositories.

Each indexed source file stores a SHA-256 content digest. Rebuilds reparse all selected files in a changed package together and reuse parser records for unchanged packages; stats reports reused_files and rebuilt_packages. Precise builds reuse that AST work but still recompute repository-wide type/CHA/SSA enrichment so cross-package dispatch remains correct.

Low-memory mode preserves those graph semantics while using more aggressive garbage collection, reclaiming memory between production and test analysis, and avoiding a full JSON copy of the AST graph. --max-memory accepts integer byte sizes such as 1GB or 1GiB and requires --memory-mode=low. It is a soft Go-runtime memory target—not a hard RSS cap—so memory-mapped files, the executable, and Go toolchain subprocesses can make process memory exceed the requested value. Aggressive GC can increase CPU time, and a target that is too low may make the build much slower or fail; Gograph never silently reduces precision to meet it.

Machine-readable structural validation

External consumers can validate one closed structural predicate without parsing human CLI output:

gograph version --json
gograph validate --repo /work/project --binding-json '{"schema_version":"gograph.binding.v1","predicate":"symbol_exists","subject":{"language":"go","kind":"symbol","id":"example.com/project/internal/auth::Authorize"},"required_precision":"ast"}' --json

The version and result schemas are gograph.version.v1 and gograph.validation.v1; bindings use gograph.binding.v1. V1 supports only symbol_exists, package_imports, call_edge_exists, and type_implements. Validation is read-only and never builds or refreshes the graph. Exit 0 means pass, exit 1 means a conclusively evaluated fail, and exit 2 means cannot_evaluate or an invalid request.

Negative results require predicate-specific completeness: symbol and direct import absence need a current complete AST graph; implementation absence needs a current precise-complete graph; call absence additionally requires complete resolution of the subject's relevant call edges. Missing, stale, partial, ambiguous, or unresolved evidence degrades to cannot_evaluate; a precise_fallback graph may support AST presence but never evaluated absence. The result binds the exact graph bytes, selected source/build-context manifest, and canonical binding with SHA-256 fingerprints.

Gograph validates selected-build-context Go structure. It does not prove runtime behavior or business correctness. CHA edges are possible static targets, not runtime dispatch certainty. V1 excludes reachability, unstable or external symbol identities, unnamed types, and non-Go languages. See the exact machine-validation contract. Applicable local module/workspace source roots must remain beneath the explicit --repo root; v1 returns cannot_evaluate instead of widening that authority.

MCP refreshes stay in memory by default. To publish each successful refresh for CLI consumers and later server processes, start the server explicitly with:

gograph mcp . --persist-refresh
# Optional low-memory policy for startup analysis and later refreshes:
gograph mcp . --memory-mode=low --max-memory=1GiB

This opt-in mode writes or overwrites .gograph/graph.json and the nine Markdown reports after a confirmed-fresh refresh. It does not modify .gitignore, so ignore .gograph/ yourself before enabling it when needed. The directory holds only the latest published state; it is not a per-branch cache. If no usable graph exists (including an unsafe or unsupported artifact), the startup auto-build is published before serving; a failure there prevents startup. A later tool-triggered publication failure makes that tool return an error, and the server retries the pending publication on another refresh-capable call without rebuilding the already-fresh in-memory graph. Writers coordinate through a local .gograph/.artifacts.lock file; an existing lock entry must be regular rather than a link or special file. Reports are replaced first and graph.json is replaced last as the publication commit marker; the complete ten-file bundle is not a single atomic filesystem transaction. Same-directory replacement is atomic on Unix-like systems; Go does not guarantee atomic rename semantics on non-Unix platforms. The lock file remains as operational coordination state in addition to the ten outputs.

Why gograph?

Illustrative point-in-time output comparison from an earlier gograph revision (counts vary as the repository evolves; these commands return different kinds of evidence):

Key Features

Machine and Agent Workflows — callers, callees, reverse test coverage, stable symbol identity, impact, context, plan, review, flow, errorflow, structural validation, orphans, hotspot, coupling, and more. The MCP server registers 67 endpoints including four session lifecycle tools. Full command reference →

Federated Workspaces — model multiple checked-out repositories through independently fingerprinted repository graphs plus a small deterministic cross-repository overlay. Resolution scopes support alternative fleets such as OSS/CE without merging repository ownership. P0 resolves Go modules, ordinary cross-repository Go calls, and first-class HTTP contracts for workspace-wide status, query, path, and impact analysis. The four read-only workspace MCP tools return the same native result values as CLI --json; member refresh and overlay publication remain explicit CLI mutations. Workspace guide →

Native MCP Server — all 63 repository query, analysis, and workflow capabilities have project-MCP equivalents for Claude, Cursor, Copilot, and other MCP clients; four additional endpoints cover session lifecycle (67 project tools total). A separate workspace server provides status, query, path, and impact with the same native results as the corresponding CLI operations. The normal mapping is CLI <command> to MCP gograph_<command>; contract, boundaries --create, and session actions use the documented special mappings. CLI-only process/host/artifact operations are build, validate, doctor, gate, snapshot, plugin/hook installation, project/workspace MCP startup, workspace build/member refresh, help, and version. Transport presentation differs where appropriate, but paired operations share functional semantics. Complete CLI/MCP matrix →

Explicit Freshness Model — CLI graph-backed analysis reads the last trusted persisted graph. gograph stale compares selected source content digests plus the effective build/module fingerprint; mtimes are diagnostic only for current indexes. It is a tri-state predicate in text and JSON modes: exit 0 means current, 2 means stale, and 1 means an operational or JSON serialization error; a missing or unsupported source-policy marker is an explicit status-1 rebuild requirement. MCP source-analysis tools check the same freshness per call, adopt a newer persisted precise graph, and incrementally rebuild changed package ASTs in memory using the latest requested analysis mode. MCP stale, default changes, and stats inspect the trusted persisted snapshot, or the startup auto-build fallback when no usable artifact exists. With --persist-refresh, that snapshot advances after a successful refresh, so default changes compares against the newly published state and normally no longer reports that refresh's source edits.

Compact Composite Workflows — context, plan, and explain combine source and graph evidence that would otherwise require several separate queries. Actual tool-call and token savings depend on the repository and task.

Narrow by Design — never runs target repository binaries or tests and does not intentionally scan .env, key, certificate, or credential files. Descendant links and special files for recognized Go build inputs are excluded; on-demand source and snippet reads use a repository-rooted filesystem handle and accept only regular .go files without symlink components. Linked/non-regular Go module/workspace metadata, sums, and vendor/modules.txt are rejected before toolchain use. Applicable workspace members must stay beneath the workspace directory, and their directories plus module metadata are preflighted before cmd/go. Default/relative policy configs are project-confined; documented absolute config/output arguments are explicit operator-selected local locations. AI worktree directories (.claude/, .cursor/, .agents/) are excluded. The installed Go toolchain resolves effective build context during indexing; precise repository package loading and external go doc run only after a preflight that rejects source-tree links cmd/go may inspect across the selected root plus its effective module root, or the workspace root and member trees, excluding .git and .gograph. Dependency and toolchain resolution remain open-world under the user's Go environment.

Architecture Enforcement — boundary rules, API drift detection, complexity gates, dead code sweeps, god-object detection, coupling analysis. Run in CI with gograph gate.

Security Flow Analysis — flow follows potential HTTP request, decoded JSON, and environment data across assignments and function calls to SQL query text, process execution, filesystem paths, and outbound HTTP targets. Findings include severity, confidence, and source-to-sink path steps; MCP exposes the same analysis as gograph_flow.

Integrity-Aware Indexing — publication refuses a linked or non-directory .gograph; graph.json is staged and replaced last only after a successful parse (the same-directory rename is atomic on Unix-like systems), records complete/partial build health and ast/precise/precise_fallback analysis status, and exposes both through gograph stats. gate refuses to evaluate a stale graph.

Agent Compliance Auditing — session telemetry tracks whether agents run plan before edits and review after. Grades agent behavior A–F with actionable recommendations.

Command Reference

Query and composed-analysis commands support --json; version --json and validate ... --json use their dedicated machine schemas. The exact --files-only surface is listed in the command reference. Operational commands such as build, wiki, gate, snapshot, installation, and help use text output; doctor and workspace build/status/query/path/impact also accept --json, and session audit additionally supports raw JSON. CLI --mermaid renders callers, callees, impact, endpoint, dependents, deps, path, and coupling as fenced Mermaid. Their MCP equivalents accept mermaid=true and return the same Markdown-fenced Mermaid text; without it, each tool retains its normal response format.

Full command reference with examples: gograph.identuum.ai/docs/command-reference

{
  "layers": [
    { "name": "domain", "packages": ["internal/domain/**"], "may_import": [] },
    { "name": "handler", "packages": ["internal/handler/**"], "may_import": ["internal/service/**", "internal/domain/**"] }
  ]
}

{
  "sanitizers": [
    { "function": "security.CleanPath", "for": ["filesystem"] },
    { "function": "security.ValidateURL", "for": ["outbound_http"] }
  ]
}

AI Agent Integration

Official MCP Registry (preview): MCPB-capable clients can discover io.github.ozgurcd/gograph. The bundle asks for the root directory of the Go project and launches the bundled executable with separate arguments equivalent to gograph mcp <project-directory>. Releases provide macOS, Linux, and Windows bundles for both amd64 and arm64. The current Registry package schema cannot select by CPU architecture, so choose the asset whose filename matches the host; do not assume a client will select it automatically. All analysis still runs locally over stdio, with no hosted gograph service or remote telemetry.

The Registry bundle and installer-generated MCP registrations intentionally omit --persist-refresh, keeping disk publication off by default. Use a custom local MCP command if you explicitly want that behavior.

Desktop config, shared rules, and Claude Code hook setup:

gograph add-claude-plugin

This registers the Claude Desktop MCP server, injects shared CLAUDE.md steering rules, and installs a Claude Code PreToolUse hook. The hook redirects Go-symbol searches only when an effective search target belongs to a repository with a .gograph index, so unindexed folders in multi-root workspaces remain unaffected. For Claude Code MCP registration, also run the command printed by the installer: claude mcp add gograph -- gograph mcp .. The installer exits non-zero when any installation step fails.

Alternative — install via Claude Code plugin marketplace:

/plugin marketplace add ozgurcd/gograph
/plugin install gograph@gograph

Discovers gograph through Claude Code's plugin marketplace and ships a SKILL.md that auto-activates on Go work, teaching the agent the workflow (doctor --json → capabilities → stats → plan → context → edit → review), when a durable precise CLI build is useful, when to use structural queries, and when to verify with gopls or targeted text/source search.

You still need the gograph binary installed (brew install --cask ozgurcd/tap/gograph or go install github.com/ozgurcd/gograph/cmd/gograph@latest). Use gograph add-claude-plugin for Claude Desktop MCP wiring plus shared rules and the Claude Code hook; register the Claude Code MCP server with the printed claude mcp add command. Use the plugin marketplace when you prefer discovery from Claude Code's plugin UI.

Other agents (Cursor, Copilot, Antigravity, etc.):

gograph mcp .                     # stdio server; refreshes stay in memory
gograph mcp . --persist-refresh   # opt in to publishing refreshed artifacts
gograph mcp . --memory-mode=low --max-memory=1GiB  # same low-memory refresh policy as CLI builds

Add to your .cursorrules or AI system prompt:

Before answering architecture or repository questions, inspect the available gograph_* MCP tools and run gograph capabilities. Prefer gograph for supported structural queries; use gopls or targeted source/text search when results are ambiguous, precision fell back, or a known source call is missing.

Query and composed-analysis commands support --json for machine-readable output:

gograph callers "YourSymbol" --json
# → {"schema_version": "1", "command": "callers", "status": "ok", "count": 2, "results": [...]}

For full integration guides, see docs/coding-agent-usage.md.

Zero-cost orientation with llm-wiki/: Run gograph wiki once per session to generate a directory of machine-first markdown pages — overview, architecture diagram, hotspots, routes, env vars, error sites, concurrency, per-package docs, and the full API surface. Agents read these pages instead of issuing dozens of individual tool calls:

gograph build . --precise
gograph wiki                 # writes to ./llm-wiki/
# generated orientation starts at: llm-wiki/overview.md
# if maintained governance pages exist, read:
# llm-wiki/index.md → project.md → agent-rules.md → agent-contract.md

Add generated wiki output to .gitignore when it is disposable. Do not overwrite a repository's maintained or Scrinium-protected agent-rules.md; propose governed changes through that repository's documented workflow.

Example Output

When you run gograph build ., the generated GRAPH_REPORT.md gives your AI a condensed context map:

External Dependencies (Tech Stack)

Important Symbols (Top by outgoing calls)

How does gograph complement gopls?

gopls is the Go project's compiler-backed language server. It provides live workspace diagnostics, navigation, references, implementations, refactoring support, and an experimental MCP server. It should remain the first choice for editor and compiler-aware workspace operations.

gograph adds a different layer for repository and agent workflows:

1. Persisted snapshots — CLI analysis can inspect a stable graph artifact, while MCP refreshes source-analysis state and preserves the requested precision mode.
2. Repository-level analyses — change impact, reachability, routes, SQL, environment reads, security-flow candidates, coupling, and policy gates are represented together.
3. Composed responses — context, plan, review, and summary package related evidence for agent workflows rather than exposing only one language operation at a time.

Use gopls for live compiler-backed navigation and refactoring, rg for text and non-Go searches, and gograph when a persisted repository graph or composed change-analysis workflow is useful. See the benchmark guidance for how to measure these different workflows without assuming one tool is a drop-in replacement for another.

Contributing

Pull requests welcome! See CONTRIBUTING.md for build, test, and contribution guidelines.

Language Support: gograph currently parses Go only. The architecture is extensible — if you want to add Python, TypeScript, Rust, etc., please open an issue first.

License

MIT — see LICENSE.