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

With no annotations, the description carries the behavioral burden. It discloses that 'comments' is a count rather than text, that visibility to the token is a precondition, and that important context may live in the comment thread rather than the description. It does not describe error behavior or response shape, but it covers the most misleading gotcha.

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 dense but every sentence earns its place: purpose, field scope, visibility condition, and a critical caveat about comments. It is structured so that the core retrieval purpose comes first, with the behavioral warning immediately after.

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 single-parameter read tool with no output schema and no annotations, the description covers what is returned, the visibility condition, and the critical comments-count caveat. It does not specify error handling or exact response structure, but an agent has enough to invoke and interpret the result correctly in most cases.

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 already fully describes the only parameter 'key' at 100% coverage with an example. The description reinforces that the key identifies the issue and determines visibility, but adds no substantial parameter syntax or format information beyond the schema.

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?

States a specific verb and resource: 'Get one issue by key'. It lists the exact fields returned (description, status, assignee, labels, sub-tasks, links, wiki pages) and the visibility condition, which clearly differentiates it from broader tools like search_issues or get_comments.

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?

Provides explicit guidance to use get_comments whenever the comments count is non-zero, explaining why the thread often contains key information. It also implies a without-visibility condition ('if visible to this token'), but does not explicitly cover when to prefer search_issues over this tool.

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