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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful context not in annotations: that the payload contains personal data (PII handling implication) and the exact fields returned, including delivery outcome and photo/signature links.

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?

One dense sentence plus the endpoint template. The resource enumeration is long but each field listed earns its place by compensating for the absent output schema. Front-loaded with the resource identity before the field list.

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 carries the return-value burden and discharges it by enumerating the key returned fields. Combined with annotations covering the read-only profile and the PII warning, an agent has enough to call it correctly; only auth/permission details are missing.

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 50%: stop_id is documented with format examples ('xyz' or 'plans/abc/stops/xyz'), but plan_id has no schema description. The description's path template (GET /plans/{planId}/stops/{stopId}) confirms both parameters' roles but adds no new syntax or constraint detail, so this stays at baseline.

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+resource: retrieves a single stop of a plan, and enumerates the resource contents (address, recipient, timing, ETA, route, delivery outcome). The singular 'One stop' implicitly distinguishes it from list_plan_stops/search_stops, but no sibling is named explicitly.

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?

No when-to-use guidance and no alternatives named. The agent must infer from the endpoint template GET /plans/{planId}/stops/{stopId} that this is a single-item fetch versus the list/search siblings. No exclusions or prerequisites are given.

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