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

Annotations already declare readOnlyHint and openWorldHint, so "Read-only" is redundant, but the description adds real value by disclosing the return contents (description, state, assignee, recent comments) and the underlying GraphQL operation. It stops short of noting comment-count limits or truncation behavior.

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?

Three compact clauses, zero padding, with the core action and key format front-loaded before the read-only and GraphQL details. Every sentence earns its place.

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?

There is no output schema, so the description usefully compensates by listing what is returned (including comments) and the query it maps to. It is nearly complete, lacking only edge-case behavior such as error handling for unknown identifiers or comment truncation.

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?

With a single parameter at 100% schema description coverage, the schema already documents the id field, and the description's identifier example merely mirrors it. Baseline 3 is appropriate since the 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?

States a specific verb (Fetch) and resource (a single issue) and names the exact lookup keys (UUID or human identifier like "ENG-123"). The word "single" clearly distinguishes it from sibling bulk/list tools such as linear_search_issues and linear_my_issues.

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?

Usage is implied by "by its UUID or human identifier" — it is the tool to use when you already hold an identifier. However, it never explicitly says when to prefer it over linear_search_issues or what to do if you only have free text, so the agent must infer the boundary.

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