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

No annotations are present, so the description carries the full burden of behavioral disclosure. It does reveal that the key is discarded, which is a useful privacy-related behavior, but it does not state whether the check is local, whether any network access occurs, or what the tool returns. The disclosure is too thin for a tool with no annotation safety profile.

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 short and front-loaded, with no filler or redundant phrasing. The second sentence 'Key discarded.' earns its place as a behavioral hint, though the space could have been better used to name the input parameter.

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 checker with no output schema and no annotations, the description should state the expected key pattern, the input property, and the return/result behavior. The current description only gives a purpose clause and a discard note, leaving important invocation details unspecified. The large generic schema makes this incompleteness more harmful.

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 description refers to a 'key', but the input schema exposes no property named 'key' and instead lists seven unrelated strings such as city, feed, host, and json. The only clue is the `ref` parameter description mentioning 'discarded after the shape check', which aligns loosely with 'Key discarded', but the description itself never maps the Jira key to a concrete input. This ambiguity makes correct invocation unreliable.

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 verb and resource: 'Check a Jira issue key shape.' This clearly distinguishes it from sibling shape-check tools like github-repo-shape, domain-shape, or wiki-title-ok. The disposal note adds a small extra behavioral fact, though it doesn't specify the return value.

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 its use case: validating the shape of a Jira issue key. However, it gives no explicit when-to-use or when-not-to-use guidance, nor names alternatives or edge cases where another tool would be better. The context is implied rather than stated.

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