Workflows Mcp Server

@cyanheads/workflows-mcp-server Store, query, and create YAML workflow playbooks for LLM agents via MCP. STDIO or Streamable HTTP. 4 Tools

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[](https://github.com/cyanheads/workflows-mcp-server/releases/latest/download/workflows-mcp-server.mcpb) [](https://cursor.com/en/install-mcp?name=workflows-mcp-server&config=eyJjb21tYW5kIjoibnB4IiwiYXJncyI6WyIteSIsIkBjeWFuaGVhZHMvd29ya2Zsb3dzLW1jcC1zZXJ2ZXIiXX0=) [](https://vscode.dev/redirect?url=vscode:mcp/install?%7B%22name%22%3A%22workflows-mcp-server%22%2C%22command%22%3A%22npx%22%2C%22args%22%3A%5B%22-y%22%2C%22%40cyanheads%2Fworkflows-mcp-server%22%5D%7D)

[](https://www.npmjs.com/package/@cyanheads/mcp-ts-core)

---

Tools

Four tools covering the full workflow library lifecycle — discovery, retrieval, and creation for both permanent and temporary workflows:

| Tool | Description | |:-----|:------------| | workflow_list | List all permanent workflows in the index, with optional category and tag filters. | | workflow_get | Retrieve a complete workflow definition by name, with global instructions prepended. | | workflow_create | Write a new permanent workflow YAML to the library. | | workflow_create_temp | Write a temporary one-shot workflow, indexed but excluded from list results. |

workflow_list

List permanent workflows from the in-memory index.

• Optional category filter (case-insensitive substring match)
• Optional tag filter (AND match — all listed tags must be present)
• Set includeTools: true to surface the unique server/tool pairs used across each workflow's steps
• Temporary workflows are excluded; results sorted by name then version descending

---

workflow_get

Retrieve a complete workflow by name, including the global instructions document.

• Semver-aware: omit version to get the highest available match; specify a version for an exact lookup
• Returns the full workflow YAML structure with all steps and metadata
• Injects the global_instructions.md content as globalInstructions — apply these when executing the workflow; null when the file is absent
• Temporary workflows are accessible here even though excluded from workflow_list
• Template placeholders ({{input.foo}}, {{steps.X.output.Y}}) are returned verbatim — the server never interpolates them

---

workflow_create

Write a new permanent workflow to the library.

• Workflow stored at categories//-workflow.yaml
• Rejects if name@version already exists — bump the version to create a new revision
• Server stamps created_date and last_updated_date automatically
• Index and snapshot rebuilt after write; filesystem watcher also fires (idempotent, debounced)

---

workflow_create_temp

Write a throwaway workflow to the temp/ directory.

• No conflict check — temp workflows are intentionally ephemeral and overwriteable
• Indexed and accessible via workflow_get but excluded from workflow_list results
• Useful for one-shot plans, short-lived scaffolding, or session-specific orchestration steps

---

Features

Built on @cyanheads/mcp-ts-core:

• Declarative tool definitions — single file per primitive, framework handles registration and validation
• Unified error handling — handlers throw, framework catches, classifies, and formats
• Pluggable auth: none, jwt, oauth
• Swappable storage backends: in-memory, filesystem, Supabase, Cloudflare KV/R2/D1
• Structured logging with optional OpenTelemetry tracing
• STDIO and Streamable HTTP transports

Workflow library:

• In-memory index keyed by name@version, built at startup from workflows-yaml/categories/ recursively
• Semver-aware lookup — latest version returned when version is omitted
• Filesystem watcher (Node.js fs.watch recursive) rebuilds the index on any add/change/remove; debounced to avoid thrash
• YAML validated at index time — invalid files are skipped and logged, never crash the server
• _index.json snapshot written on every rebuild for external tooling and debugging
• Configurable WORKFLOWS_DIR, GLOBAL_INSTRUCTIONS_PATH, and debounce interval

Agent-friendly output:

• workflow_get always includes globalInstructions alongside the workflow — no second call needed
• Discriminated source field (permanent | temp) on every workflow_get response
• Typed error contracts with structured reason codes (not_found, version_not_found, already_exists, index_unavailable) so callers can branch on error type rather than parsing messages
• workflow_list with includeTools: true surfaces all MCP server/tool dependencies at a glance

---

Getting started

No API keys required. The server reads from a local workflows-yaml/ directory by default.

Add the following to your MCP client configuration file:

{
  "mcpServers": {
    "workflows-mcp-server": {
      "type": "stdio",
      "command": "bunx",
      "args": ["@cyanheads/workflows-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "WORKFLOWS_DIR": "/absolute/path/to/your/workflows-yaml"
      }
    }
  }
}

Or with npx (no Bun required):

{
  "mcpServers": {
    "workflows-mcp-server": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@cyanheads/workflows-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "WORKFLOWS_DIR": "/absolute/path/to/your/workflows-yaml"
      }
    }
  }
}

Or with Docker:

{
  "mcpServers": {
    "workflows-mcp-server": {
      "type": "stdio",
      "command": "docker",
      "args": [
        "run", "-i", "--rm",
        "-e", "MCP_TRANSPORT_TYPE=stdio",
        "-v", "/absolute/path/to/your/workflows-yaml:/workflows-yaml",
        "-e", "WORKFLOWS_DIR=/workflows-yaml",
        "ghcr.io/cyanheads/workflows-mcp-server:latest"
      ]
    }
  }
}

For Streamable HTTP, set the transport and start the server:

MCP_TRANSPORT_TYPE=http MCP_HTTP_PORT=3010 bun run start:http
# Server listens at http://localhost:3010/mcp

Seed workflows

The repository ships a workflows-yaml/ directory with example workflows organized under categories/. These are ready to use as a starting point. The workflows-yaml/global_instructions.md file contains instructions the server prepends to every workflow_get response — edit it to set global guidance for your agent.

Prerequisites

• Bun v1.3.2 or higher (or Node.js v24+).
• A local directory containing YAML workflow files (or use the bundled workflows-yaml/ seed).

Installation

1. Clone the repository:

git clone https://github.com/cyanheads/workflows-mcp-server.git

1. Navigate into the directory:

cd workflows-mcp-server

1. Install dependencies:

bun install

1. Configure environment:

cp .env.example .env
# edit .env if needed — most settings have defaults

---

Configuration

| Variable | Description | Default | |:---------|:------------|:--------| | WORKFLOWS_DIR | Absolute or relative path to the workflows root directory. | ./workflows-yaml | | GLOBAL_INSTRUCTIONS_PATH | Path to the global instructions markdown file. Derives from WORKFLOWS_DIR when not set. | /global_instructions.md | | WATCHER_DEBOUNCE_MS | Milliseconds to debounce filesystem change events before rebuilding the index. | 500 | | MCP_TRANSPORT_TYPE | Transport: stdio or http. | stdio | | MCP_HTTP_PORT | Port for HTTP server. | 3010 | | MCP_AUTH_MODE | Auth mode: none, jwt, or oauth. | none | | MCP_LOG_LEVEL | Log level (RFC 5424). | info | | OTEL_ENABLED | Enable OpenTelemetry instrumentation (spans, metrics, completion logs). | false |

See [.env.example](./.env.example) for the full list of optional overrides.

---

Running the server

Local development

• Build and run:

```sh # One-time build bun run rebuild

# Run the built server bun run start:stdio # or bun run start:http ```

• Run checks and tests:

``sh bun run devcheck # Lint, format, typecheck, security bun run test # Vitest test suite bun run lint:mcp # Validate MCP definitions against spec ``

Docker

docker build -t workflows-mcp-server .
docker run --rm \
  -v /path/to/workflows-yaml:/workflows-yaml \
  -e WORKFLOWS_DIR=/workflows-yaml \
  -p 3010:3010 \
  workflows-mcp-server

The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/workflows-mcp-server. OpenTelemetry peer dependencies are installed by default — build with --build-arg OTEL_ENABLED=false to omit them.

---

Project structure

| Directory | Purpose | |:----------|:--------| | src/index.ts | createApp() entry point — registers tools and inits the workflow index service. | | src/config/ | Server-specific environment variable parsing and validation with Zod. | | src/mcp-server/tools/ | Tool definitions (*.tool.ts). | | src/services/workflow-index/ | WorkflowIndexService — YAML parsing, index build, watcher, semver lookup, write helpers. | | tests/ | Unit and integration tests mirroring src/. | | workflows-yaml/ | Seed workflow library — categories/ for permanent workflows, temp/ for throwaway ones, global_instructions.md for agent-global guidance. |

---

Development guide

See [CLAUDE.md](./CLAUDE.md) for development guidelines and architectural rules. The short version:

• Handlers throw, framework catches — no try/catch in tool logic
• Use ctx.log for request-scoped logging
• Register new tools via the barrel in src/mcp-server/tools/definitions/index.ts
• Filesystem operations go through WorkflowIndexService, not directly in tool handlers

---

Contributing

Issues and pull requests are welcome. Run checks and tests before submitting:

bun run devcheck
bun run test

---

License

Apache-2.0 — see [LICENSE](LICENSE) for details.

Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: cyanheads
• Source: cyanheads/workflows-mcp-server
• License: Apache-2.0
• Homepage: https://www.npmjs.com/package/@cyanheads/workflows-mcp-server

Install and usage instructions live in the source repository linked above.