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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the description's job is the non-obvious logic, and it delivers: the result is the cheapest qualifying plan, non-fitting plans carry reason codes, and the status flips to needs_sales on total failure. It stops short of naming the actual return fields beyond reason code and status.

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?

A single dense sentence with the outcome front-loaded and no filler. The parenthetical about fetch frequency and runtime earns its place; the semicolon-joined needs_sales clause is slightly compressed but not wasteful.

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?

For a 5-parameter tool with no output schema, the description covers the decision logic, the failure mode, and partial return shape. The remaining gaps are the undocumented departure_stations parameter and the full response structure, which is a minor shortfall rather than a blocking one.

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?

With 0% schema description coverage the description must carry the load, and it partially does: screens are glossed as fetch frequency and runtime, and content/locations/dpa are named. However departure_stations is never mentioned, and 'dpa volume' does not clearly map to the dpa_requests_per_day parameter or its unit.

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 outcome: the cheapest self-service plan satisfying given screen/content/location/dpa requirements, plus reason codes and a needs_sales status when nothing fits. The 'self-service' qualifier implicitly separates it from request_enterprise_quote, though no sibling is named explicitly. An agent can tell what it computes without opening the schema.

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?

There is no explicit 'use this when' or 'use X instead' statement. The 'self-service' framing and the 'needs_sales when none does' outcome hint that enterprise-sized requirements route elsewhere, but the agent must infer that escalation path rather than being told it.

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