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

With no annotations provided, the description carries the full burden. It discloses that the tool is free, that it returns only keys and nesting (never values), that the match score threshold is >=0.95 healthy, and that the data is observed from paid replies. It does not mention rate limits or failure modes, but the key behavioral constraints are clearly stated.

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 compact and front-loaded with the most important fact ('FREE', 'trust check'). It packs a lot of useful detail into a short space. The only minor issue is the slightly dense phrasing around 'advertised-shape match score', but overall every sentence earns its place.

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 tool has an output schema, so return values are covered. The description explains the purpose, the key parameters, the use case, and the behavioral constraints. It could mention what happens if no paid calls exist for a slug, but for a read-only snapshot tool with an output schema, this is adequate.

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 0%, so the description must compensate. It explains the 'slug' parameter by listing valid agent slugs and explains 'n' implicitly via 'last N paid x402 calls'. It does not give the exact type/format of slug, but the example list and context make the parameter semantics reasonably clear.

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 states a specific verb ('get'), a resource ('capability snapshot'), and the exact scope: observed response structure of the last N paid x402 calls for an agent, keyed by settlement tx, with keys/nesting only. It also names concrete outputs (top JSON paths, match score, latest settlement tx) and example slugs, which distinguishes it from sibling tools like get_agent_credit_score or check_x402_endpoint.

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?

The description explicitly says 'Check BEFORE paying' and frames the tool as a trust check for paid agents on AgentPayStore. It also lists the applicable slugs (forge, cipher, duke, gridiron, wally, odds, scout and other AgentPayStore agents), giving an agent clear conditions for when to invoke this tool versus alternatives.

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