Why MCP Tool Descriptions Must Be Engineered as Strict Machine Contracts
The Model Context Protocol has effectively turned internal scripts and database actions into APIs consumed not by human developers but by AI agents reading tool descriptions at runtime. Unlike human developers who can seek clarification or apply judgment, agents act immediately on their interpretation of a tool's name, schema, and description — repeating any misreading at scale across every session. Ambiguities that cost a human developer a support thread can cost an AI-driven system cascading incorrect actions multiplied across hundreds of automated calls per hour. Experts recommend encoding constraints directly into JSON Schema using enums, patterns, and explicit field types rather than relying on prose descriptions, and structuring outputs with stable machine-readable fields so agents can reliably chain follow-up actions. Error responses must also map to specific recovery actions, and any field renaming or structural output change should be treated as a breaking API change, since agents will silently fail with no ability to flag degraded behavior.
This is an AI-generated summary. ShortSingh links to the original source for the complete article.

Discussion (0)
Log in to join the discussion and vote.
Log in