flood_risk_by_postcode

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

With no annotations, the description fully carries the burden of transparency. It discloses the output (highest risk band, address counts per band, groundwater indication) and the honest 'not found' response. It also highlights limitations. It does not discuss authentication or rate limits, but for a simple query tool, this is adequate.

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 concise and well-structured, using a bold 'IMPORTANT' section for key constraints. Every sentence adds value, with 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?

Given the tool's simplicity (one parameter, no output schema), the description is complete enough. It explains the output structure, limitations, and error behavior. Lack of detailed output schema is acceptable because the description covers the key return fields.

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 schema covers the single parameter with example format, but the description adds the critical constraint that it is for England postcodes only, clarifying the geographic scope. This adds meaningful value beyond the schema.

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 retrieves the Environment Agency's long-term flood-risk indication for an England postcode. It specifies the verb 'get' and the resource, and distinguishes from the sibling 'validate_postcode' by describing its function as returning risk bands rather than validation.

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 tells when to use the tool ('USE THIS to get ... instead of guessing') and provides concrete use cases (triaging insurance quotes, underwriting). It also states limitations (England only, area-level not property-level, long-term risk not live warning). However, it does not explicitly mention when not to use or alternatives beyond the sibling.

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