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

Annotations already declare readOnlyHint and destructiveHint, so the safety profile is clear. The description adds crucial context: it's a data/research tool over TED, no guarantee of award, returns only top lanes, and includes total count in coverage. No contradictions.

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 a single paragraph with no fluff. It front-loads the action and then explains scope and limitations. Every sentence serves a purpose. Could be slightly more structured but is efficient.

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?

With no output schema, the description only vaguely indicates the return (top-ranked lanes, total count in coverage.lanes_ranked). It mentions metrics but not the exact output structure. More detail on return format would improve completeness.

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% and the description adds value by explaining the purpose of min_n ('Drop lanes thinner than this (honest: small n = noise)') and the limit's role. This enriches understanding 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 uses a specific verb ('Rank CPV sector lanes') and clearly states the resource and metrics. It distinguishes from siblings by explicitly noting it does not estimate win probability, differentiating from find_winnable_lanes.

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 tells when to use the tool ('where is competition thinnest right now') and what it does NOT do (win forecast), helping avoid misuse. It does not explicitly mention alternative tools or when to use them, but the contrast with win probability is strong guidance.

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