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

The description adds substantial behavior beyond the annotations: it discloses that the action re-POSTs the payload, may bill again, charges 0.01 credits per successful forward, requires an API key, and fails closed on billing errors. This is exactly the kind of destructive and financial side-effect context an agent needs.

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?

The description is compact and front-loaded with the primary purpose, followed by auth, cost, side effects, and usage caution. Every sentence contributes essential information, and the destructive warning is prominently placed. No filler or repetition.

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, non-idempotent, billing-sensitive tool, the description covers purpose, prerequisites, cost, side effects, failure behavior, and when it is appropriate to call. The output schema exists, so omitting return-value details is acceptable. The description is complete for safe invocation.

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?

The schema covers 100% of the single parameter with a clear description and example. The description merely restates 'required id (delivery id),' which adds no meaning beyond the schema. Baseline 3 is appropriate given the high schema coverage.

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 opens with a specific verb and resource: 'Replay a stored webhook delivery through the same forward/retry pipeline.' It also states the intended context ('after your consumer was down'), which distinguishes it from a generic send tool like relay.webhook. This is clear, specific, and not a tautology.

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 usage context: use after the consumer was down and 'Prefer after confirmed consumer recovery.' It warns not to call casually. However, it does not explicitly name alternatives or state when not to use it versus relay.webhook, so it falls just short of full guidance.

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