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

Goes well beyond the annotations by disclosing a concrete rate limit ('2 keys per address per day'), the credential nature of the output ('Treat the key like a password'), and that no email or card is required. This is exactly the operational context the readOnlyHint/destructiveHint flags cannot convey.

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?

Three short sentences, front-loaded with the outcome (a free key) before the usage instructions and constraints. Every clause carries distinct information with no repetition of the title.

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?

An output schema exists so return values need no prose, and the description covers the rate limit, security handling, and next steps. It omits lifetime/expiry of the key and whether the 100 rows are one-time, minor gaps for a credential-issuing tool.

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?

The tool takes zero parameters, so the baseline is 4 and there is nothing for the description to disambiguate. The mention of 'api_key' refers to downstream tools, not to this tool's input, so it neither helps nor misleads here.

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 and resource ('Returns a Hunch key') with a quantified scope ('100 free rows') and the distinguishing condition ('no email and no card'). This clearly separates it from the sibling tools, which all consume rather than issue credentials.

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?

Explicitly states the context of use ('For the keyless /mcp/try connection') and what to do with the result ('pass the key as api_key to the other tools, or reconnect with it'). It does not say when not to call it (e.g., if a key already exists), which keeps it short of a 5.

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