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

Annotations already flag destructiveHint=true and idempotentHint=false, but the description adds genuinely new context: user approval and `confirmed=true` are required, credits may be consumed, and writes are never retried automatically (explaining why manual redelivery exists). It stops short of describing what a redelivery produces or any rate limits.

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?

Four short sentences, front-loaded with the core action, then the bulk-mode rule, then the safety gate. No filler or restated 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 destructive mutation with no output schema, it covers the approval gate, bulk behavior, and credit implications. It omits what the redelivery returns or whether a new delivery record/id is created, which would help an agent report results.

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 only 33% schema coverage, the description carries real weight: it documents the `delivery_id=all` sentinel value combined with `since`, a semantics the schema does not express, and reiterates the `confirmed` gate. The `id` (webhook) parameter is left to the schema's example description.

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?

Specific verb (redeliver) plus resource (a webhook delivery), and it immediately clarifies the scope: queue one delivery to be sent again, or all deliveries after a timestamp. An agent can distinguish it from the read-only `get_webhooks_id_deliveries_delivery_id` sibling without opening either 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?

Gives clear conditions for the two modes (single `delivery_id` vs `delivery_id=all` with `since`) and states the approval prerequisite (`confirmed=true`). It does not name a sibling alternative for inspecting deliveries first, so it stops short of a 5.

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