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

Annotations already declare readOnlyHint=true, destructiveHint=false and non-open-world, so the safety profile is covered. The description adds real behavioral value by disclosing the returned fields, including the cross-reference to which pipelines use each endpoint. It does not say whether archived endpoints are excluded or whether results paginate, so it adds some but not rich context.

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?

A single front-loaded sentence with zero filler; the verb and resource come first and the parenthetical clarification earns its place by defining an ambiguous domain term. Nothing could be cut without losing meaning.

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, the description must carry the return-shape burden, and it does so by naming the key fields the agent will see. For a parameterless list tool this is nearly complete; only filtering/pagination behavior is unstated.

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 zero parameters, so per the baseline this scores 4. The description wisely spends its words on output content instead of nonexistent inputs, describing key, active revision, and pipeline usage.

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+resource ('List webhook endpoints') and even defines the concept in a parenthetical ('the URLs a pipeline's webhook block can ask for an outcome'), which is genuinely useful domain framing. It also previews what each entry contains (key, active revision, using pipelines), which helps distinguish it from get_webhook_endpoint and list_webhook_endpoint_revisions. It stops short of naming siblings explicitly, so it stays at 4.

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?

There is no explicit when-to-use or when-not-to-use guidance and no named alternative among the many webhook siblings (get_webhook_endpoint, list_webhook_endpoint_revisions, list_webhook_endpoint_uses). The plural 'List' with no parameters implies an enumeration call, but the agent must infer that this is the browse-all entry point. Minimum-viable implied usage.

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