decimalai-mcp
Part of DecimalAI. Most users want the Python SDK → decimal-labs/decimalai-python.
MCP server for the DecimalAI skills registry — the registry that ranks agent skills by measured effectiveness (verified A/B benchmarks, live pass rates, AI rater scores), not download counts.
Gives any MCP client (Claude Desktop, Claude Code, Cursor, …) three read-only tools:
| Tool | What it does |
|---|---|
search_skills(query, category?, sort?, limit?) |
Hybrid keyword/semantic search over the public registry |
get_skill(slug) |
Full record: trust & safety-scan status, verified benchmark lift, SkillScore, ratings, SKILL.md body |
get_leaderboard(sort?, category?, window_days?, limit?) |
Ranked leaderboard: skill_score, biggest_improvement, efficiency, top_rated |
No API key required — all three tools read public registry endpoints. If you set DECIMAL_API_KEY (from app.decimal.ai/settings), the same tools additionally show which skills your org has already installed (installed_as).
Install
pip install decimalai-mcp
# or, no install needed at config time:
uvx decimalai-mcp
Requires Python 3.10+.
Claude Code
claude mcp add decimalai -- uvx decimalai-mcp
# with an API key:
claude mcp add decimalai -e DECIMAL_API_KEY=dai_sk_... -- uvx decimalai-mcp
Claude Desktop
Add to claude_desktop_config.json (Settings → Developer → Edit Config):
{
"mcpServers": {
"decimalai": {
"command": "uvx",
"args": ["decimalai-mcp"],
"env": {
"DECIMAL_API_KEY": "dai_sk_optional"
}
}
}
}
Omit the env block entirely for anonymous read-only access.
Configuration
| Env var | Default | Purpose |
|---|---|---|
DECIMAL_API_KEY |
(unset) | Optional. Unlocks per-org enrichment (e.g. installed_as) on the same public endpoints. |
DECIMAL_API_URL |
https://api.decimal.ai |
Point at a self-hosted / local backend. |
Why no check_manifest_impact tool?
The manifest-impact endpoint (POST /api/v1/regression-check) is authenticated on the platform — it analyzes your org's production traces against a candidate manifest, so there is no public variant to expose. This server is deliberately a read-only, key-optional public-registry surface. If demand shows up, an authed check_manifest_impact (requiring DECIMAL_API_KEY) is a natural v0.2 addition; the regression-check GitHub Action covers the CI use-case today.
Endpoints used (all public)
GET /api/v1/registry/skills— browse/searchGET /api/v1/registry/skills/{slug}— detailGET /api/v1/registry/leaderboard— ranked leaderboard (categoryfiltering falls back to the browse endpoint's documentedview=ranksmode, because the leaderboard endpoint is uncategorized)
Development
pip install -e ".[dev]"
pytest # all HTTP mocked; no network
python -m decimalai_mcp.server # run over stdio
Run pytest yourself before opening a PR. CI also asserts that the pinned mcp<2 still provides FastMCP, which the mocked tests do not cover — run that one too:
python -c "from mcp.server.fastmcp import FastMCP; import decimalai_mcp.server"
Releases are cut from a published GitHub Release — see
RELEASING.md for the gates a
change has to pass and the version strings that must move together.
License
MIT