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

The readOnlyHint annotation already covers the read-only nature, and the description adds valuable context about the status filter (failed or still retrying). However, it does not disclose other behaviors such as pagination, ordering, or error conditions, so it meets but does not exceed the bar given the annotation.

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 sentence, 18 words, with no filler. The action and filter are front-loaded, and the sentence is easy to parse. Every word contributes to the 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?

For a simple filtered-list tool with a readOnly annotation and one required parameter, the description provides enough to understand the core purpose but lacks guidance on parameter usage (especially limit and appSlug format) and alternatives. The missing usage guidelines and parameter semantics prevent full completeness for an agent to call it without extra schema inspection.

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 description coverage is only 33% (only api_key has a description), and the tool description adds minimal parameter meaning beyond echoing 'given app' for appSlug. It does not explain limit semantics or the role of appSlug further, failing to compensate for the low schema coverage.

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 uses a specific verb ('Show') and a resource ('events for the given app') with a clear filter ('not successfully reached any destination'). It distinguishes this from sibling list tools like anyhook_events or anyhook_inbox by explicitly scoping to undelivered events, so an agent can identify the tool's niche.

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?

The description implies the use case (retrieve undelivered events) but does not explicitly compare with alternatives or state when not to use it. It lacks explicit exclusions or references to sibling tools, leaving the agent to infer the appropriate scenario.

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