dsh-plugins

Composable, config-driven plugins for DeepSeek Harness (dsh). Each package is a publishable dsh bundle: install only what an agent needs, configure it through Cordis, and keep dsh itself unpatched.

Packages

Package	What it does	Primary seams
@amaster.ai/dsh-a2a	Serves dsh agents over the A2A protocol 1.0 (JSON-RPC + SSE, with a v0.3 compatibility layer): streaming turns, task cancel, task list, agent card; pluggable task-state stores (memory/Redis/GCS + workspace archive)	ctx.agents, session/event, own HTTP server
@amaster.ai/dsh-storage	Mirrors the session event stream into MySQL/PostgreSQL/SQLite/SQL Server (ai_messages / ai_chat_histories)	session/event tap (local persistence stays authoritative)
@amaster.ai/dsh-langfuse	Langfuse observability: one generation per LLM call (plus a nested llm-request span with the verbatim loop-built request), one span per tool call, one trace per turn; subagent child sessions nested under the parent's tree	llm/stream + tools/execute waterfalls, session/event, session/created + subagent/start/subagent/end

Plugin previews

dsh-a2a

dsh-storage

dsh-langfuse

Status

This is an early dsh-preview ecosystem. The plugin shapes, config schemas, and seam choices are in place; event-payload field names are marked TODO(verify) where dsh pre-release APIs may shift. Pin your dsh version and check those markers before production use.

Compatibility

@amaster.ai/dsh-*	dsh	cordis	@a2a-js/sdk (dsh-a2a)
0.1.x	0.1.0-rc.7 (source) / 0.1.0-rc.7 (npm)	^4.0.1	^1.1.0 (A2A 1.0 + v0.3 compat)

dsh is in developer preview and will break compatibility between releases. Every release of these plugins pins a tested dsh version in this matrix; upgrade deliberately.

Install

Every package is a dsh bundle and ships a cordis.patch.yml. With the dsh CLI:

dsh plugin --profile my-agent add @amaster.ai/dsh-a2a @amaster.ai/dsh-storage @amaster.ai/dsh-langfuse
dsh --profile my-agent

For local development from this checkout, use a --patch overlay instead (no packaging needed):

# dev.patch.yml
- insert:
    - id: langfuse
      name: file:///absolute/path/to/dsh-plugins/packages/dsh-langfuse

dsh --profile my-agent --patch dev.patch.yml

Configuration

All three plugins are disabled by default and configured through the standard dsh plugin config layer (Schemastery-validated, hot-reloaded). Example profile cordis.patch.yml snippet:

- insert:
    - id: langfuse
      name: '@amaster.ai/dsh-langfuse'
      config:
        enabled: true
        publicKey: pk-lf-...
        secretKey: sk-lf-...
        baseUrl: https://cloud.langfuse.com
    - id: storage-mirror
      name: '@amaster.ai/dsh-storage'
      config:
        enabled: true
        database:
          enabled: true
          provider: mysql   # mysql | postgresql | sqlite | sqlserver
          url: mysql://user:pass@host:3306/agent
    - id: a2a
      name: '@amaster.ai/dsh-a2a'
      config:
        enabled: true
        host: 127.0.0.1   # no auth built in — keep loopback or front with a proxy
        port: 41241
        cwd: /srv/agent-workspaces
        taskStore: redis  # memory | redis | gcs — A2A task state only
        redis:
          url: redis://127.0.0.1:6379
        gcs:
          bucket: my-agent-archives

Data model

dsh-storage's relational shape matches the source project's ai_messages / ai_chat_histories tables, so existing data stays compatible (one deviation: no user_id column — tenancy rides on session_id). It requires Prisma 7 peer packages at runtime: @prisma/client plus the driver adapter for your database (@prisma/adapter-mariadb for MySQL, @prisma/adapter-pg for PostgreSQL, @prisma/adapter-libsql for SQLite, @prisma/adapter-mssql for SQL Server). The PrismaClient is pre-generated per provider and shipped in the package — no prisma generate step. Create or upgrade the tables with the shipped schema variant:

npx prisma db push --schema node_modules/@amaster.ai/dsh-storage/prisma/schema.mysql.prisma --url "mysql://user:pass@host:3306/agent"
# schema.postgresql.prisma / schema.sqlite.prisma / schema.sqlserver.prisma work the same way

SQL Server note: Prisma's sqlserver connector has no Json type, so its variant maps the JSON columns to text — the backend serializes them on write automatically (derived from provider: sqlserver; SQL Server's ISJSON / JSON_VALUE still query the text as JSON).

• ai_messages — one row per projected session event (user / model / tool), with thoughts, tokens, tool_calls, agent_id, metadata JSON columns and soft-delete.
• ai_chat_histories — per-session rollup (message count, total tokens, first/last message timestamps).

The logical message id rides in metadata.id; message rows use a deterministic hash of (session_id, message id) as their primary key, so re-projected events upsert in place rather than duplicate — on every connector (the source project's metadata.id JSON-path lookup only works on PostgreSQL/MySQL). Session rows are matched by session_id and keep their cuid primary keys — the per-session serialization chain makes the find-then-write safe, and rows from the early scaffold (or the source project) are continued, never duplicated. Upgrade note: the early scaffold wrote messages with cuid keys; if you ran it, dedupe those by metadata.id before enabling this version.

A2A task state is a separate concern from conversation history: dsh-a2a ships pluggable TaskStore backends — in-memory (default), Redis (task state JSON + TTL), and GCS (gzipped task state, same object layout as the source project's GCSTaskStore). Every backend persists a metadata shell only (history/artifacts are stripped before saving — conversation history belongs to dsh-storage), and saves are collapsed to task-state transitions so streamed text deltas never reach the backend.

Security

dsh ships no authentication or authorization. dsh-a2a binds 127.0.0.1 by default; if you expose it, put an authenticated reverse proxy in front and treat every agent as running with the host process's OS privileges. Multi-tenant deployments need per-tenant isolation (containers) on top.

Repository layout

packages/
├── dsh-a2a/        # A2A protocol server plugin
├── dsh-storage/    # session storage mirror plugin (+ prisma schema)
└── dsh-langfuse/   # Langfuse observability plugin

Development

pnpm install
pnpm build        # tsc per package
pnpm typecheck
pnpm test         # vitest (packages with a test script)

Current limitations

• All plugins are disabled by default; enable and configure each explicitly in the profile.

• dsh-a2a is text-only at the protocol boundary (non-text message parts are rejected), has no approval/input-required mid-turn bridge (dsh rc.7 ships none), and does not resume live sessions across restarts — persisted task shells survive in Redis/GCS, but continuing a conversation starts a fresh session. No event replay is retained for subscriptions: SubscribeToTask opens with the current task snapshot and follows the live bus only.

• dsh-a2a GCS store: workspace archiving (archiveWorkspace) shells out to tar and is not wired to the task lifecycle yet.

License

MIT