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

Annotations already establish readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds real context beyond that: a hard cap of 5 endpoints, the specific fields returned including failure counters, and the non-obvious side effect of also returning the full event-type catalog, which an agent would otherwise not anticipate.

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 compact sentences with zero filler, front-loaded with what the tool returns and its scope limit. The secondary return (event-type catalog) is appended in a separate sentence so it does not obscure the primary result.

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?

There is no output schema, so the description carries the burden of explaining return values, and it does so concretely for all the listed fields plus the extra catalog. For a zero-parameter read tool with a hard cap of 5 items, nothing material is missing—no pagination or filtering concerns arise.

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 the schema imposes nothing for the description to clarify. Baseline 4 applies, and the description correctly spends its words on return content rather than inventing parameter guidance.

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 (webhook endpoints) and scopes it to the caller's own endpoints, capped at 5, which tells an agent this is a listing operation distinct from get_webhook (single), create_webhook, and delete_webhook. It never uses an explicit verb like 'list', but the plural possessive framing makes the purpose unambiguous in practice.

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: an agent can infer this is the tool to inspect existing webhook configuration, but the description never states when to prefer it over get_webhook or webhook-adjacent siblings, nor any preconditions. No alternatives or exclusions are offered.

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