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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is fully covered by structured data. The description adds that each entry includes 'delivery health diagnostics', which is genuine behavioral context about the result content, though an output schema exists that likely documents this already. No disclosure of auth requirements, limits on number of targets returned, or how health is computed.

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 the resource, scope, and output content in that order; no filler, hedging, or restatement of the title.

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 zero-parameter, read-only list tool with both annotations and an output schema, the description covers who the results belong to and what they contain, which is most of what an agent needs. The only real gap is routing guidance versus kellian_get_webhook and kellian_discover_webhooks, which is a sibling-selection concern rather than a completeness defect.

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 there is nothing for the description to disambiguate and the baseline is 4. The description correctly implies an unfiltered, unpaginated listing of the caller's own targets, consistent with the empty input schema.

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 (List) and resource (webhook delivery targets) plus the ownership scope ('owned by the authenticated agent'), which distinguishes it from kellian_get_webhook (single target) and kellian_discover_webhooks. It does not explicitly name those siblings, so the differentiation is inferable rather than stated.

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 by the ownership scope: an agent can infer it lists its own webhooks rather than fetching one by id or discovering others'. There is no explicit when-to-use statement, no mention of kellian_get_webhook or kellian_discover_webhooks as alternatives, and no preconditions (e.g. whether webhooks must be configured first).

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