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

The only disclosed behavioral trait is 'Key discarded,' which suggests the input is not retained. But with no annotations and no output schema, the description does not explain what a 'shape check' returns, what counts as valid, or how errors are surfaced. The agent is left guessing about observable behavior.

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 extremely short and front-loads the core purpose. It contains no filler, and the second sentence does add a behavioral note about discarding the input. It loses one point because the brevity leaves 'Key discarded' ambiguous and does not compensate for the schema mismatch.

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 tool with nine parameters, no annotations, and no output schema, this description is severely incomplete. It does not specify the expected Jira key format, which parameter to pass, what the result looks like, or whether the check returns a boolean or an error. An agent cannot reliably invoke this tool based on the provided definition.

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?

Although every schema parameter has a description, the description refers to a 'key' that does not appear anywhere in the input schema. The schema exposes ref, url, city, feed, host, json, path, zone, and query, none of which is identified as the Jira key. The description fails to resolve this mismatch, so an agent cannot know which parameter to populate.

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 clearly states the operation and target: 'Check a Jira issue key shape.' This is specific enough to distinguish it from sibling shape-checkers like domain-shape, figma-url-shape, and github-repo-shape, since it names the exact resource type being validated.

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 when to use the tool: when an agent needs to validate the shape of a Jira issue key. However, it provides no explicit guidance about when not to use it, nor does it mention alternatives from the sibling list.

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