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

With no annotations, the description carries the full burden of disclosing behavior. It only states that the key is 'discarded', implying no persistence, but omits any details about return values (e.g., boolean, error object), side effects, or how validation results are communicated. This is a significant gap for a tool whose primary purpose is validation.

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 brief, but brevity is not conciseness when it omits essential information. It lacks structure—no breakdown of purpose, usage, or output. While it wastes no words, it fails to communicate necessary details, making it under-specified rather than efficiently concise.

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 parameters, no output schema, and no annotations, the description is grossly incomplete. It does not explain what 'shape' means, what a valid Jira key looks like, what the tool returns (e.g., true/false, error messages), or how the various parameters relate to the check. An agent would have no idea how to interpret results or handle edge cases. This is a major gap in usability.

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 input schema provides descriptions for all 9 parameters, achieving 100% coverage. The tool description adds nothing beyond the schema, but since the schema is thorough, the parameters are adequately documented. The phrase 'Key discarded' might relate to the ref or query, but it is not clear enough to enhance parameter understanding. Baseline 3 is appropriate because schema does the heavy lifting.

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 ('Check') and resource ('Jira issue key shape'), which is clearer than a tautology. However, it does not define what constitutes a valid 'shape' (e.g., project key + issue number format), nor does it differentiate itself from sibling shape tools like github-repo-shape or domain-shape. The phrase 'Key discarded' hints at a validation-only purpose but leaves the actual check criteria undefined.

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 provided on when to use this tool versus the many sibling shape-validation tools. There is no mention of prerequisites, context, or alternatives. The description gives no signal about what kind of input this expects or how it fits into a workflow, leaving the agent to infer applicability from the name alone.

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