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

Annotations already establish readOnly, idempotent, non-destructive, so the safety profile is covered. The description adds real value beyond that: it enumerates the returned per-webhook fields (delivery status, consecutive failures, disabled flag) and explicitly notes the secret is never returned, which tells the agent what it cannot retrieve here.

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?

Two sentences, front-loaded with the resource and scope, followed by the returned fields. Every clause carries information; the closing "Never the secret" earns its place as a security caveat rather than filler.

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 no output schema and zero parameters, the description must carry the return-value burden, and it does by naming the fields returned and the field withheld. A brief note on ordering or pagination behavior would close the remaining gap, but for a simple zero-arg read this is close to sufficient.

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 tool takes no parameters, so there is nothing for the description to disambiguate and the baseline of 4 applies. The implicit constraint that results are scoped to the calling key is a useful extra, though not a parameter explanation.

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 names the resource precisely and adds a real scope constraint: these are only the webhooks this key registered, traced back to create_event_webhook. It lacks an explicit verb ("list"), but an agent can still tell this apart from create/delete siblings from the text alone.

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?

Usage is only implied: you read this to see the lifecycle state of webhooks you created via create_event_webhook. There is no explicit when-to-use/when-not-to-use statement and no pointer to delete_event_webhook for cleanup, so the agent must infer the workflow.

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