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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that the input key is discarded, which is useful privacy context, but does not disclose whether the result is a boolean, normalized key, or error, nor behavior on malformed 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?

Two short sentences with no filler; the key action is front-loaded. 'Key discarded.' is slightly cryptic but still concise and informative about side-effect behavior.

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 validation tool with no output schema, the description should state what the caller receives (e.g., a boolean or pass/fail status) and how to interpret the check. The description also does not clarify which of the many schema properties is relevant, leaving the agent with an unusually broad, ambiguous input schema.

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 description coverage is effectively 100% and the relevant 'jira' parameter is described as 'Jira issue key e.g. PROJ-123', so the baseline is met. The tool description adds no parameter information; the unrelated schema fields create some ambiguity about which input to supply, but the schema and name make the intended parameter inferable.

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 verb and object: 'Check a Jira issue key shape.' This clearly identifies the resource and distinguishes it from sibling shape-checkers by domain (Jira key). It lacks an explicit statement of what result is returned, which keeps it short of 5.

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 for when to call this tool instead of an alternative. There are no conditions, exclusions, or comparison to sibling tools such as github-repo-shape or wiki-title-ok; usage is only implied by the tool name.

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