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

It discloses several behavioral traits beyond annotations: limit of 50 entries, newest-first order, potential latency ('A refusal can take a moment to appear'), required token permissions ('update on the list'), and request cost ('1 request'). It doesn't explain output format, but an output schema exists.

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?

The description is a single tight paragraph, front-loaded with the key action and result, and every sentence adds useful information without repetition or fluff.

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?

Given the simple input schema, read-only annotations, and the presence of an output schema, the description is nearly complete. It covers the data returned, latency, relevant sibling tool, and auth needs. One minor gap: it doesn't mention that the list must exist, but that's inferred.

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?

With 100% schema description coverage for the single parameter, the baseline is 3. The description adds practical context about the parameter's role (the list whose rules refused writes) and clarifies that the token needs update permission, which is not in the 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?

The description states a specific resource and scope: 'the last 50 writes the list's write rules refused, newest first.' It precisely distinguishes itself from sibling tools like list_events and test_list_rules by focusing on denied write attempts and their details.

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?

It provides clear context for when to use it (inspecting rule denials) and directs the agent to use test_list_rules for replaying a denial. However, it does not explicitly state when not to use it or compare to other diagnostic tools like get_event.

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