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

With no annotations present, the description must carry the behavioral disclosure burden, but it only says 'Key discarded.' That hints at no persistence, yet does not explain the expected response, errors, network behavior, or side effects. It also never maps the discarded key to any parameter in the schema.

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 text is short and front-loaded; it states an intended action in two sentences without fluff. It loses the top score because brevity comes at the cost of context, especially given 9 parameters and no output schema.

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 9 optional parameters, no required fields, and no output schema, the description is incomplete. It does not explain which parameter to populate, what kind of Jira key shape is matched, what the tool returns, or what 'discarded' means operationally. The context provided is insufficient for reliable invocation.

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 descriptions cover 100% of the parameters, so a baseline of 3 is appropriate. However, the description adds little semantic mapping: there is no parameter named 'key' or 'issue_key' in the input schema, and most schema descriptions refer to unrelated concerns such as URLs, paths, timezone, cities, and JSON; an agent cannot tell which parameter is the key to check.

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 names a specific action and resource: checking a Jira issue key's shape, which is clear and helps distinguish it from sibling shape-checkers such as domain-shape or github-repo-shape. It stops short of a top score because it says nothing about which input parameter is the key and introduces the puzzling phrase 'Key discarded' without explaining the Jira key relationship.

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?

No guidance is given about when to use this tool versus alternatives, when not to use it, or what to do with the result. The intended use is only implicit in the verb phrase 'Check a Jira issue key shape'; there are no prerequisites or alternative relationships mentioned.

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