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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds useful context beyond those annotations by stating that the tool returns "the full issue record" and that the issue comes from "the connected account," which is helpful given there is no output schema. It does not mention not-found or error behavior, but that is a minor gap for a simple read-only fetch.

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 four short sentences, each earning its place: the action, the return value, the parameter provenance, and the routing rule to the alternative tool. There is no filler, tautology, or restatement of the title.

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 one-parameter, read-only get tool, the description covers what it does, what it returns, where the id comes from, and when to use the sibling list tool instead. The absence of an output schema is partially mitigated by stating "Returns the full issue record." It lacks detail on error responses or not-found behavior, but those are unlikely to prevent correct selection and invocation.

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% and the sole parameter already has a clear description, so the baseline is 3. The description adds extra meaning by explaining that the id is obtained from list_unified_issues, which tells the agent it is a previously returned unified issue ID rather than an arbitrary search key. No further format or validation details are needed for a single string ID.

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 opens with a specific verb and resource: "Retrieve a single issue by its ID from the connected account." It also distinguishes this tool from list_unified_issues by making clear that this is ID-based retrieval rather than listing or searching, so an agent can tell them apart without inspecting schemas.

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?

It gives an explicit condition: "Use when you already have the ID; to search or list issues, use list_unified_issues." It also states the required ID is obtained from list_unified_issues, effectively telling the agent when not to use this tool and which sibling to choose instead.

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