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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the baseline is covered. The description adds genuine non-obvious context beyond them: that the returned procedure is grounded in the mock event as the source of truth and that provider payloads are deliberately not fabricated, which sets expectations about what the guide contains.

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 sentences, front-loaded with the core purpose and then the procedure and the rationale. Each sentence carries information, though the middle procedural sentence is slightly dense and reads more like a workflow note than a tool definition.

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 one-parameter read-only guide tool with a fully documented schema and no output schema, the description covers purpose, the surrounding workflow, and the key caveat about not fabricating payloads. Only minor ambiguity remains about what the returned procedure text looks like and whether any prerequisite (such as a Mock account) can block the call.

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 single destination_id parameter is documented thoroughly, including the warning not to use a remote endpoint ID. The description adds no further meaning about the parameter, so the schema does all the work and the baseline of 3 applies.

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 first sentence gives a precise verb and resource ('Return the exact test procedure for a destination'), which is clearly distinct from sibling tools like webhook_get_delivery_logs or webhook_delete_destination. It does not, however, contrast itself with the nearby webhook_get_setup_guide, which an agent could easily confuse with a test guide.

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 lays out an explicit usage sequence: generate a mock/test event with a Mock account, then inspect webhook_get_delivery_logs and the target runtime. That tells the agent the context in which this tool belongs, though it stops short of stating when to prefer it over webhook_get_setup_guide or what to do if no mock account exists.

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