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

No annotations are provided, so the description carries the full burden. It discloses that the tool runs as a background job (async), returns a jobId, and requires polling via get_job_result. This adequately informs the agent about the tool's behavior beyond what annotations would provide.

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 two sentences, front-loaded with purpose and then usage hint. Every sentence adds value with no waste.

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 no output schema, the description adequately explains the return value (jobId) and the need to poll get_job_result. It also mentions the output includes GBP prices and booking links. Some information about pagination or rate limits is missing, but overall it's sufficient.

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 100%, so the schema already documents parameters. The description adds minimal extra meaning beyond the schema, such as 'must be real calendar dates (2026-02-30 is rejected)' for dates, but this is marginal. Baseline 3 is appropriate.

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 it explores cheapest destinations worldwide from an origin on given dates, with live GBP prices and booking links. The phrase 'Great for "where can I fly cheaply" questions' distinguishes it from sibling tools like search_flights or search_stopover_itineraries.

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 states it is great for 'where can I fly cheaply' questions and that it runs as a background job returning a jobId, with instruction to poll get_job_result until done. However, it does not explicitly state when not to use it or compare directly to siblings.

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