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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), but the description adds genuinely new context: result ordering, the fields returned per entry, the required API-key scope `webhooks:read`, and the page-size ceiling. It does not discuss failure modes for an unknown webhookIdentifier, but the added auth-scope disclosure is real value beyond structured fields.

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 purpose and result shape before pagination and auth details. Minor noise: the `page` reference that has no matching schema property and the unexplained omission of the `limit` alias, which cost a point of precision.

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 read-only paged list with a fully documented schema and no output schema, the description covers ordering, entry contents, pagination and auth scope, which is what an agent needs. The unresolved `page` versus `cursor`/`limit` naming is the only real ambiguity.

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 would be 3; the description earns a bump by clarifying pagination semantics (cursor or page, size max 100, default backend-defined). The mention of `page` is slightly at odds with the schema, which only exposes `cursor`, `size` and the `limit` alias.

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 ('List recent delivery attempts for a webhook') plus ordering ('most recent first'), and enumerates what each entry contains. An agent can immediately separate it from pm_get_webhook (config), pm_list_webhooks (enumeration) and pm_replay_webhook_delivery (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 an explicit use case — 'diagnosing why a subscriber is missing events' — which tells the agent when this is the right tool. It stops short of naming alternatives such as pm_replay_webhook_delivery for retrying or pm_get_webhook for configuration, so the when-not side is left implicit.

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