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

Annotations already declare readOnly, idempotent, open-world, non-destructive, so the safety profile is covered. The description adds real value by saying it draws on live evidence and explicitly does not fabricate a score or winner, which sets expectations for the output. It does not say anything about latency, cost, coverage limits, or what the evidence looks like.

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?

Two short sentences, front-loaded with the verb and arity, with no filler. Every clause 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?

For an open-world comparison tool with no output schema, the definition leaves too much unresolved: target format, what 'live evidence' is returned, and expected latency. Annotations cover safety but not the information an agent needs to prepare inputs or interpret results.

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 coverage is 0%, so the description must carry parameter meaning. It explains the 2-5 count (matching minItems/maxItems), but never says what a 'target' string actually is — provider name, ID, or URL — despite a minLength that suggests a structured identifier. That gap is the main thing an agent needs clarified.

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 (compare) and resource (providers) with an explicit 2-5 arity bound, so the agent can tell it is a multi-provider comparison rather than a single-provider check like verify_provider. It does not explicitly name the sibling it displaces, so it stops short of a 5.

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 arity '2-5 providers' implies the shape of a valid call, but there is no statement of when to choose this over verify_provider, check_identity, or check_payment, and no exclusions or prerequisites. The agent must infer the routing decision from sibling names alone.

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