units-static

High-quality unit conversion MCP server with fixed conversion tables (no network I/O). Companion dogfood to meteo-static: this repo is the good MCP baseline — tools are designed so schema-clarity judges should score well (clear names, deep descriptions, strict enums, typed output schemas).

Tools

Tool	Description
list_units	List supported unit ids (optionally filter by dimension)
convert_length	Convert length between SI / imperial units
convert_mass	Convert mass / weight
convert_temperature	Convert °C / °F / K (rejects below absolute zero)
convert_volume	Convert liquid volume (US + imperial + SI)
compare_quantities	Compare two quantities in the same dimension

Design goals (judge-friendly)

• Names: lowercase, descriptive, verb-led (convert_*, list_*, compare_*)
• Descriptions: when to call the tool, what it does, what not to use it for
• Inputs: closed enums / constrained fields with per-parameter descriptions
• Outputs: Pydantic models → MCP outputSchema objects (no bare arrays)
• Deterministic: static factor tables; safe for CI evals

Running

STDIO (default)

pip install -r requirements.txt
python src/server.py

Streamable HTTP

pip install -r requirements.txt
python src/server.py --transport http --port 8000

Export tools/list (local)

pip install -r requirements.txt
python scripts/export_tools_list.py --output ci/tools-list.json

GitHub Actions

Shared Actions from plugin-federation/actions:

Job	Purpose
tools-list-validate	Export tools/list + structural validation
nexus-catalog	OIDC → catalog + embeddings + LLM-as-judge (fail-on-judge-fail)
evals	Functional evals (evals/evaluations.xml, 100% threshold)

Nexus pipeline setup

Variable / secret	Purpose
NEXUS_URL	e.g. https://api.nonprod.plugin-federation.com
NEXUS_OIDC_AUDIENCE	Must match Nexus GitHub audience
TENANT_ID	Target tenant UUID
MCP_SOURCE_ID	New stable tool source UUID for this server
XAI_API_KEY	Judge model + functional evals
OPENAI_API_KEY	Embeddings (text-embedding-3-small)

Also register this repository in the tenant OIDC trust policy (same pattern as meteo-static) and create a dedicated tool source for units-static.

Status

• Working — stdio + streamable HTTP
• Tools — six conversion tools with structured I/O
• CI — Plugin Federation Actions with hard fail gates