Example MCP Server node for Tagentacle (Streamable HTTP)
Single tool 'get_weather' has a clear action verb name and basic description. However, the tool lacks parameter type hints in the schema (Pydantic Field annotation present but not visible as JSON Schema in registration), output schema is not documented, and error handling is minimal. The mock implementation and straightforward functionality prevent this from being rated lower, but production readiness gaps are significant.
Get current weather for a given city (mock data)
Parameter schema lacks explicit type documentation. Input uses Pydantic Field annotation but JSON Schema representation is inferred from type hints; no explicit schema document visible showing 'type': 'string' for 'city' parameter.
Output schema not documented. Tool returns a plain string ('Weather in {city}: {result}') with no structured schema definition or type annotation. LLMs cannot plan downstream operations or extract specific fields.
Parameter description is minimal (10 chars: 'City name'). Rubric baseline is 72 chars average; this one is far below. Does not specify format, valid city examples, or what happens if the city is not in WEATHER_DATA.
No error guidance or recovery paths. Tool returns a fallback string for unknown cities but does not signal success vs. fallback to the LLM. Agents cannot distinguish 'real data' from 'no data' responses.
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-22 | C | 60 | 2026-07-28+ | v2 |
| 2026-03-09 | F | 44 | - | v1 |
Tool description does not clarify that it returns mock data and covers only a hardcoded set of cities. This is important context, LLMs will otherwise assume comprehensive global coverage.