Replay request

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

Annotations already declare readOnlyHint=false and openWorldHint=true, so the agent knows this mutates external state. The description adds that the call goes to the 'real backend' and returns the upstream response, which partly compensates for the missing output schema, but it says nothing about side effects persisting upstream, auth requirements, or failure behavior.

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?

Two tight sentences: the core action leads, followed by the override caveat and the use case. No filler or restatement of the title.

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 moderately complex tool with fully documented params and no output schema, the description covers action, overrides, and return. It is nearly sufficient, though error/side-effect behavior on the upstream would complete the picture.

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 baseline is 3. The description enumerates the override fields (method/url/body/headers) and calls them optional, matching the schema, but adds no syntax or format detail beyond it (e.g., the headers full-replacement nuance lives only in 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+resource ('Re-issue a captured request') and states the outcome ('return the upstream response'), making the operation unambiguous. It never names a sibling like get_request or replay_session, so the differentiation from those tools is left to inference.

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?

It gives explicit when-to-use conditions: 'verify a fix against the real backend or A/B between two URLs.' That is concrete context, but there are no exclusions or prerequisites (e.g., when to prefer get_session or replay_session instead).

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