Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower, and the description still adds real value: it discloses the return shape (findings), the chaining contract (a toolcard://answers URI to pass to resources/read), and statelessness ('Does not store the tool'). It stops short of describing severity levels or empty/failure results.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Four short sentences, front-loaded with purpose, followed by return behavior, the chaining URI, and a non-persistence guarantee. Every sentence carries distinct information with no filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

There is no output schema, so the description must carry the return-value burden, and it only partially does — 'Returns findings' and the answer-URI pattern are covered, but finding structure, severity, and counts are not. For a nested-object input with no output schema, this is adequate but not complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The description restates which fields are checked (name, description, inputSchema) but adds no format, validation, or edge-case guidance beyond what the schema properties already document.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (check) and resource (one MCP tool name, description, and input schema) against 'Toolcard cited rules'. The word 'one' implicitly separates it from the server-scoped sibling check_server, though it never names that sibling outright.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied by the purpose — validate a single tool definition — but there is no explicit when-to-use, when-not-to-use, or pointer to check_server for server-level validation. An agent must infer the scoping distinction between the two check_* tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.