Mastodon Blade MCP

A security-first, token-efficient MCP server for Mastodon. 45 tools across timelines, statuses, notifications, search, and social interactions.

Why another Mastodon MCP?

	The-Focus-AI/mastodon-mcp	cameronrye/activitypub-mcp	This
Tools	~4 (minimal)	53 (ActivityPub-generic)	45 (Mastodon-targeted)
Token cost	Full JSON dumps	Verbose output	Pipe-delimited, HTML-stripped
Write safety	None	None	Write gate + confirm gate
Rate limiting	None	None	X-RateLimit-* header parsing, adaptive backoff
Multi-instance	Single only	Single	Native multi-instance
Notifications	None	Basic	Full filtering by type
Credential safety	N/A	N/A	Scrubbed from all output

This MCP is designed for agentic platforms that need:

• Precise reads -- query one status, one thread, one hashtag. No full-state dumps.
• Safe writes -- two-tier gating (env var + per-call confirm) for destructive operations.
• Multi-instance -- manage multiple Mastodon servers from a single MCP.
• Token efficiency -- pipe-delimited output, HTML stripping, null-field omission.
• Rate limit awareness -- parses Mastodon headers, warns at thresholds, backs off when exhausted.

Quick Start

Install

# With uv (recommended)
uv tool install mastodon-blade-mcp

# Or from source
git clone https://github.com/groupthink-dev/mastodon-blade-mcp.git
cd mastodon-blade-mcp
make install

Configure

# Single instance
export MASTODON_INSTANCE="https://mastodon.social"
export MASTODON_TOKEN="your-access-token"

# Multi-instance
export MASTODON_PROVIDERS="social,hachyderm"
export MASTODON_SOCIAL_INSTANCE="https://mastodon.social"
export MASTODON_SOCIAL_TOKEN="token-for-social"
export MASTODON_HACHYDERM_INSTANCE="https://hachyderm.io"
export MASTODON_HACHYDERM_TOKEN="token-for-hachyderm"

# Enable posting, favouriting, following (disabled by default)
export MASTODON_WRITE_ENABLED="true"

Create an access token at Preferences > Development > New Application on your Mastodon instance.

Run

# stdio (default -- for Claude Code, Claude Desktop)
mastodon-blade-mcp

# HTTP transport (for remote access)
MASTODON_MCP_TRANSPORT=http MASTODON_MCP_API_TOKEN=your-secret mastodon-blade-mcp

Claude Code Integration

{
  "mcpServers": {
    "mastodon": {
      "command": "uvx",
      "args": ["mastodon-blade-mcp"],
      "env": {
        "MASTODON_INSTANCE": "https://mastodon.social",
        "MASTODON_TOKEN": "your-token",
        "MASTODON_WRITE_ENABLED": "true"
      }
    }
  }
}

Claude Desktop Integration

{
  "mcpServers": {
    "mastodon": {
      "command": "uvx",
      "args": ["mastodon-blade-mcp"],
      "env": {
        "MASTODON_INSTANCE": "https://mastodon.social",
        "MASTODON_TOKEN": "your-token"
      }
    }
  }
}

Tools (45)

Read (25 tools)

Tool	Description	Token Cost
mastodon_info	Instance info, write gate, rate limit status	Low
mastodon_verify	Verify credentials (current user)	Low
mastodon_timeline_home	Home timeline (followed accounts)	Medium
mastodon_timeline_public	Public/federated timeline	Medium
mastodon_timeline_local	Local instance timeline	Medium
mastodon_timeline_hashtag	Hashtag timeline	Medium
mastodon_timeline_list	List timeline	Medium
mastodon_status	Get specific status by ID	Low
mastodon_context	Thread context (ancestors + descendants)	Medium
mastodon_search	Unified search (accounts/statuses/hashtags)	Medium
mastodon_account	Account info by ID	Low
mastodon_account_statuses	Account's statuses with filters	Medium
mastodon_relationships	Check relationships with accounts	Low
mastodon_followers	List followers	Medium
mastodon_following	List following	Medium
mastodon_notifications	Notifications (filterable by type)	Medium
mastodon_trending_tags	Trending hashtags	Low
mastodon_trending_statuses	Trending statuses	Medium
mastodon_trending_links	Trending links	Low
mastodon_bookmarks	Bookmarked statuses	Medium
mastodon_favourites	Favourited statuses	Medium
mastodon_lists	All lists	Low
mastodon_list_accounts	Accounts in a list	Medium
mastodon_conversations	DM conversations	Medium
mastodon_filters	Active content filters (v2)	Low

Write (20 tools -- require MASTODON_WRITE_ENABLED=true)

Tool	Description	Confirm Gate
mastodon_post	Create new status (text, CW, media, schedule)
mastodon_reply	Reply to a status
mastodon_edit	Edit existing status
mastodon_delete	Delete status	Yes
mastodon_favourite	Favourite a status
mastodon_unfavourite	Remove favourite
mastodon_boost	Reblog a status
mastodon_unboost	Remove reblog
mastodon_bookmark	Bookmark a status
mastodon_unbookmark	Remove bookmark
mastodon_pin	Pin to profile
mastodon_unpin	Unpin from profile
mastodon_follow	Follow an account
mastodon_unfollow	Unfollow an account
mastodon_block	Block an account	Yes
mastodon_unblock	Unblock an account
mastodon_mute	Mute an account (optional duration)	Yes
mastodon_unmute	Unmute an account
mastodon_dismiss_notification	Dismiss single notification
mastodon_media_upload	Upload media attachment

Output Format

All output is pipe-delimited for token efficiency:

# Status
109876543210 | @user@mastodon.social | 2026-04-04 10:30 | public | Hello world! | fav=5 | boost=2 | reply=1

# Account
@user@mastodon.social | Test User | followers=100 | following=50 | statuses=200

# Notification
99999 | mention | @other@mastodon.social | 2026-04-04 11:00 | status=109876543210 | "@user Hey there!"

# Search results
## Accounts (1)
@user@mastodon.social | Test User | followers=100 | following=50 | statuses=200
## Hashtags (1)
#python | uses_7d=42

# Thread context
## Ancestors (1)
anc-1 | @parent@mastodon.social | 2026-04-04 09:00 | public | Original post
## Descendants (2)
desc-1 | @reply1@mastodon.social | 2026-04-04 11:00 | public | First reply
desc-2 | @reply2@mastodon.social | 2026-04-04 12:00 | public | Second reply

Security Model

Layer	Mechanism
Write gate	MASTODON_WRITE_ENABLED=true env var for any mutation
Confirm gate	confirm=true parameter for delete, block, mute
Credential scrubbing	Tokens and instance URLs stripped from all error output
Bearer auth	Optional MASTODON_MCP_API_TOKEN for HTTP transport (timing-safe comparison)
Rate limiting	X-RateLimit-* header parsing with adaptive backoff
No caching	Credentials read from env at startup, never persisted

Multi-Instance Support

Target a specific instance with the instance parameter on any tool:

mastodon_timeline_home instance="social"
mastodon_timeline_home instance="hachyderm"

Omit instance to use the default (first configured) instance.

Environment Variables

Variable	Description	Required
MASTODON_INSTANCE	Instance URL (single-instance)	Yes*
MASTODON_TOKEN	OAuth access token	Yes*
MASTODON_PROVIDERS	Comma-separated provider names	No
MASTODON_{NAME}_INSTANCE	Per-provider instance URL	Per-provider
MASTODON_{NAME}_TOKEN	Per-provider token	Per-provider
MASTODON_WRITE_ENABLED	Enable write operations	No (default: false)
MASTODON_MCP_TRANSPORT	stdio or http	No (default: stdio)
MASTODON_MCP_HOST	HTTP bind address	No (default: 127.0.0.1)
MASTODON_MCP_PORT	HTTP port	No (default: 8770)
MASTODON_MCP_API_TOKEN	Bearer token for HTTP transport	No

* Required if MASTODON_PROVIDERS is not set.

Development

# Install with dev deps
make install-dev

# Run tests
make test

# Coverage report
make test-cov

# Lint + format + type check
make check

# Run the server
make run

Architecture

src/mastodon_blade_mcp/
├── server.py        -- FastMCP 2.0 server, 45 tool definitions
├── client.py        -- MastodonClient: httpx async, multi-instance
├── formatters.py    -- Token-efficient pipe-delimited output, HTML stripping
├── models.py        -- ProviderConfig, write gate, confirm gate, credential scrubbing
├── rate_limiter.py  -- X-RateLimit-* header parsing, adaptive backoff
├── auth.py          -- Bearer token middleware for HTTP transport
└── __main__.py      -- Entry point

Dependencies: fastmcp, httpx, pydantic. No Mastodon.py dependency -- pure HTTP against the Mastodon REST API.

Sidereal Marketplace

This MCP conforms to the social-v1 service contract (20/20 operations):

• Required (4/4): timeline, status, search, notifications
• Recommended (6/6): context, account, trending, bookmarks, favourites, relationships
• Optional (4/4): lists, filters, conversations, instance
• Gated (6/6): post, delete, favourite, boost, follow, block

See sidereal-plugin.yaml for the full plugin manifest.

License

MIT