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

With no annotations, the description carries the burden of disclosing side effects. It says 'Key discarded,' which hints at not retaining input, but it does not explicitly state that the operation is read-only, side-effect-free, or what happens on invalid input.

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 brief and to the point, using only two sentences. However, 'Key discarded' adds little clarity and could be replaced with more useful information.

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?

The tool context is incomplete: the description and schema are severely misaligned, no output schema is provided, and there is no indication of how the Jira key should be supplied. An agent cannot reliably call this tool correctly based on the provided information.

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 schema lists nine parameters, but none is named 'key,' and the descriptions appear unrelated to Jira issue keys (e.g., 'Git ref name,' 'City name for a public weather hint'). The tool description mentions a key, but no parameter is identified as the key input, making it impossible to know which field 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 states a specific action and object: 'Check a Jira issue key shape.' This is clear enough to distinguish the tool's core purpose from most siblings. However, the phrase 'Key discarded' is ambiguous and does not clarify whether this is a validation-only operation or something else.

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 provides no guidance on when to use this tool versus alternatives such as domain-shape, github-repo-shape, or normalize-url. It does not mention any preconditions, expected input format, or exclusions.

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