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

Annotations already declare readOnlyHint=true and openWorldHint=true, so 'Read-only' is redundant. The description does add real context the annotations cannot: the identity semantics of 'viewer' (API key owner / OAuth actor) and the underlying GraphQL call. It omits return shape and pagination behavior, and the redundancy of restating the read-only hint keeps it at a 3.

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 fragments, front-loaded with the scope before implementation detail. 'Read-only' duplicates the annotation and the raw GraphQL query string is developer-facing padding, but overall it is tight and readable.

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-optional-parameter read tool with annotations covering safety, the description covers identity and mechanism. However, no output schema exists, so the description could have described the returned issue shape or pagination, and it does not; it is adequate but not complete.

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?

Only one parameter ('first') and schema description coverage is 100%, so the schema already documents the maximum, default, and exclusivity. The description adds nothing about the parameter, which is the expected baseline when 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 (List) plus resource (issues assigned to the current user), and clarifies who 'current user' means (API key owner / OAuth actor via viewer.assignedIssues). It doesn't explicitly contrast itself with linear_search_issues, which is the sibling an agent would most likely confuse it with, so it falls short of 5.

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 scope 'assigned to the current user' implies when the tool applies, but there is no explicit when-to-use statement, no exclusions, and no pointer to alternatives such as linear_search_issues for broader querying. Usage is inferable but not stated.

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