bluesky-mcp-server

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Tools

Seven tools for read-only access to the public Bluesky/AT Protocol AppView — no authentication required:

Tool	Description
bsky_search_posts	Full-text search across public Bluesky posts, with author, language, tag, domain, date, and sort filters
bsky_get_profile	Fetch a Bluesky actor's public profile by handle or DID — the handle↔DID resolver
bsky_get_author_feed	A user's recent posts ordered newest-first, filterable by post type
bsky_get_post_thread	Fetch the full conversation for a post by AT-URI — parent chain upward and reply tree downward
bsky_search_actors	Find Bluesky accounts by name or handle fragment
bsky_get_follows	Paginated social graph edges — who a user follows or who follows them
bsky_get_trending	Real-time trending topics on Bluesky with post count, category, and status

bsky_search_posts

Full-text search across public Bluesky posts.

• Filters: author handle, language (BCP-47), hashtag, domain, date range (since/until), and sort order (top or latest)
• Returns posts with text, author, engagement counts (likes/reposts/replies/quotes), embeds, AT-URIs, and timestamps
• hitsTotal when available — total matching posts, not just the current page
• Pagination via opaque cursor; up to 100 results per call
• Embeds normalized into a flat union: images, external (link cards), record (quoted posts), video, unknown
• Moderation labels surfaced as-is — not filtered

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bsky_get_profile

Fetch a Bluesky actor's public profile by handle or DID.

• Returns displayName, handle, DID, description, follower/following/post counts, avatar URL, moderation labels, and pinned post AT-URI
• The resolution step for handle↔DID — use before tools that require a DID or AT-URI when you only have a handle

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bsky_get_author_feed

A user's recent posts ordered newest-first.

• Filter by post type: posts_with_replies, posts_no_replies, posts_with_media, or posts_and_author_threads
• Returns posts with full text, engagement counts, embeds, and AT-URIs for thread drilling
• Pagination via cursor

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bsky_get_post_thread

Fetch the full conversation for a post by AT-URI.

• Returns the root post, parent chain (upward), and nested reply tree (downward)
• Configurable depth (reply tree depth, default 6) and parent_height (parent chain height, default 80)
• Truncated subtrees surface truncated: true; deleted posts surface as not_found
• AT-URIs come from bsky_search_posts or bsky_get_author_feed

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bsky_get_follows

Fetch social graph edges for an account.

• direction: followers (who follows the actor) or following (who the actor follows)
• Returns paginated profiles with handle, DID, displayName, description, and follower count
• Includes the subject's profile summary at the top level

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bsky_get_trending

Fetch real-time trending topics on Bluesky.

• Returns topics with display name, post count, category (politics, sports, pop-culture, etc.), status (hot/rising), and start time
• No cursor — returns the current snapshot up to limit
• Uses app.bsky.unspecced.getTrends — Bluesky may change this endpoint without notice

Resource

Type	Name	Description
Resource	bsky://profile/{actor}	A Bluesky actor's public profile, addressable by handle or DID

All resource data is also reachable via tools. Use bsky_get_profile for programmatic access or bsky://profile/{actor} to inject profile context directly.

Features

Built on @cyanheads/mcp-ts-core:

• Declarative tool and resource 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

Bluesky-specific:

• No authentication required — all seven tools operate against api.bsky.app without credentials
• Single BlueskyService wrapping the AT Protocol public AppView with retry (3 attempts, 500ms base), 15s timeout, and a versioned User-Agent
• Embed normalization — raw nested AT Protocol embed objects flattened to a clean type-discriminated union
• Moderation labels surfaced verbatim — the agent and its human decide what to do
• AT Protocol identifier types (handle, DID, AT-URI) explained at first encounter in every tool description

Agent-friendly output:

• AT-URIs on every post and resource — chain bsky_search_posts → bsky_get_post_thread without extra steps
• Discriminated embed union (type: "images" | "external" | "record" | "video" | "unknown") — branch on data, not $type strings
• hitsTotal on search results — communicate result scale to users without extra round trips
• Truncation signals (truncated: true) on thread nodes — agents know where the tree ends and why

Getting started

Public Hosted Instance

Connect directly — no installation required:

{
  "mcpServers": {
    "bluesky-mcp-server": {
      "type": "streamable-http",
      "url": "https://bluesky.caseyjhand.com/mcp"
    }
  }
}

Self-hosted

Add the following to your MCP client configuration file. No API key required.

{
  "mcpServers": {
    "bluesky-mcp-server": {
      "type": "stdio",
      "command": "bunx",
      "args": ["@cyanheads/bluesky-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info"
      }
    }
  }
}

Or with npx (no Bun required):

{
  "mcpServers": {
    "bluesky-mcp-server": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@cyanheads/bluesky-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info"
      }
    }
  }
}

Or with Docker:

{
  "mcpServers": {
    "bluesky-mcp-server": {
      "type": "stdio",
      "command": "docker",
      "args": [
        "run", "-i", "--rm",
        "-e", "MCP_TRANSPORT_TYPE=stdio",
        "ghcr.io/cyanheads/bluesky-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

Prerequisites

• Bun v1.3.0 or higher (or Node.js v24+).
• No API key or account required — all tools call api.bsky.app without credentials.

Installation

1. Clone the repository:

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

2. Navigate into the directory:

cd bluesky-mcp-server

3. Install dependencies:

bun install

4. Configure environment (optional):

cp .env.example .env
# edit .env to override any framework defaults

Configuration

This server requires no API keys. All framework configuration is optional.

Variable	Description	Default
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
LOGS_DIR	Directory for log files (Node.js only)	<project-root>/logs
STORAGE_PROVIDER_TYPE	Storage backend	in-memory
OTEL_ENABLED	Enable OpenTelemetry instrumentation	false

See .env.example for the full list of optional overrides.

Running the server

Local development

• Build and run:

  # One-time build
  bun run rebuild
  
  # Run the built server
  bun run start:stdio
  # or
  bun run start:http
  

• Run checks and tests:

  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 bluesky-mcp-server .
docker run --rm -p 3010:3010 bluesky-mcp-server

The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/bluesky-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, resource, and inits service.
src/services/bluesky	AT Protocol AppView HTTP client with retry, timeout, and User-Agent.
src/mcp-server/tools	Tool definitions (*.tool.ts) — seven read-only Bluesky tools.
src/mcp-server/resources	Resource definitions (*.resource.ts) — bsky://profile/{actor}.
tests/	Unit and integration tests mirroring src/.

Development guide

See 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, ctx.state for tenant-scoped storage
• Register new tools and resources via the arrays in src/index.ts
• Wrap external API calls: validate raw → normalize to domain type → return output schema; never fabricate missing fields

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 for details.