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

Annotations cover safety (readOnly, idempotent, closed-world), and the description adds real behavioral context: a 1-credit vs 100-credit price wall and the fallback behavior for unscored leads. However, the flat "costs 100 credits" conflicts with the schema's "1 + 10 credits per scored row", leaving the true cost model ambiguous for expensive calls.

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 core action, then the cost tradeoff, then the one surprising caveat. No filler and nothing buried.

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 an output schema present, return values need not be explained, and the description covers purpose, cost, and the summary-only edge case. The unresolved discrepancy between "100 credits" and the per-row formula is the one gap an agent could stumble on.

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 100%, so baseline is 3, but the description earns an extra point by enumerating what `full` actually returns (exact score parts, every ask with link and attribution, requirements, 8-week ask counts) rather than restating the enum. The `id` parameter gets no added meaning in the description beyond what the schema already documents.

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 ("Get one gap by id or slug") and implicitly contrasts with the collection-level list_gaps sibling by emphasizing singular retrieval. An agent can tell immediately this is a single-record fetch keyed by identifier.

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?

Gives clear operational context: two detail levels with sharply different credit costs and the constraint that unscored leads only return summary, which tells the agent when the cheap call suffices. It does not explicitly name check_demand or get_dossier as alternatives or state when not to call it, so it stops 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.