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

Adds substantial context beyond the annotations: preserves event_id for deduplication, rechecks the current endpoint revision so concurrent edits are not overwritten, requires the webhook.manage permission, and inherits the tenant/agent/Live-Sandbox authorization model of /api/v1/webhooks/endpoints. None of this is derivable from the readOnly/idempotent/destructive hints.

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?

Purpose and scope are front-loaded in the first two sentences, with prerequisites, auth, and idempotency guidance following in a logical order. It is dense but every sentence carries actionable information, so only minor trimming is possible.

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 what an agent needs: the precondition, the exclusions, the required permission, the authorization model, the concurrency safeguard, and a docs link. Nothing material is missing for a 4-parameter mutation tool.

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 the baseline is 3, but the description adds real meaning: it explains that the revision is rechecked to prevent overwriting concurrent edits and that the idempotency_key must be reused verbatim after an uncertain mutation, which goes beyond the schema's field-level text.

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 ('retry a failed delivery') and immediately narrows scope by excluding successful deliveries, so an agent can distinguish it from siblings like test_webhook_endpoint or list_webhook_deliveries. The 'explicitly' framing clarifies this is a manual operator-initiated replay rather than automatic retry.

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 a clear precondition ('after correcting the receiver') and an explicit exclusion ('Does not replay successful deliveries or approve facility handling'), plus retry guidance for uncertain mutations. It stops short of naming a specific sibling alternative, so it lands just below the top band.

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