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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is clear. The description adds that it returns payment behavior and caller tier, which provides some extra context beyond annotations, but does not elaborate on side effects or details of the return. No contradiction with annotations.

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?

The description is a single sentence, front-loaded with the action. It is concise but uses the imperative 'Describe' rather than a declarative statement, which slightly reduces clarity. No wasted words.

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?

The description mentions the high-level outputs (surface, payment, caller tier) but does not detail what 'MCP surface' means or the format of the response. Without an output schema, a more explicit description of the return would improve completeness. It is adequate but leaves ambiguity.

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?

There are 0 parameters, so schema coverage is trivial (100%). The description does not need to add parameter meaning. Baseline of 4 is appropriate given no parameters.

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?

The description clearly states the tool describes the MCP surface, payment behavior, and active caller tier. It is a specific verb-resource pairing, though it could be more precise (e.g., 'returns information about...'). It distinguishes from the sibling 'research' tool by implying different functionality.

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?

No guidance on when to use this tool versus alternatives. The description does not provide context for selection or exclusions. The only sibling is 'research', but no comparison is made.

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