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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds that the response includes description, labels, and relations, which is useful but not essential. It does not mention auth, rate limits, or other behaviors, but given the annotations, the bar is met. No contradiction with annotations.

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 a single sentence with no wasted words. It front-loads the action and resource, then lists the returned fields. Efficient and to the point.

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 simple, single-parameter, read-only tool with no output schema, the description is sufficiently complete. It specifies the purpose, the identifier, and the included fields. It could mention that it returns a single object, but that is implied by 'one issue'. The annotations cover safety, so nothing critical is missing.

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 coverage is 100% with a clear description for the 'issue' parameter. The tool description restates the identifier formats but adds no new semantics beyond what the schema provides. Baseline of 3 is appropriate when the schema fully documents the parameter.

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 action ('Fetch') and the resource ('one issue'), and specifies the identifier formats ('ENG-42' or by id). It also mentions the included fields (description, labels, relations), distinguishing it from sibling tools like list_issues or search_issues that operate on collections.

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 clearly indicates when to use this tool: when you need a single issue by identifier. It does not explicitly mention alternatives or exclusions, but the specificity of 'one issue' implies it is for individual retrieval rather than listing or searching. Given the large sibling list, a note about using list_issues for multiple issues would strengthen it, but the current wording is unambiguous enough.

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