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

Annotations already declare readOnlyHint, openWorldHint=false, idempotentHint, and destructiveHint=false. The description adds genuinely useful behavior beyond those: the set is fixed, the categories are named, and the output includes a neutral description for each category. It does not discuss ordering or formatting, but those are minor for a zero-parameter read-only list.

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 dense sentence with a long parenthetical list of seven categories Dropping the list would hurt usefulness, and there is no fluff. The structure is slightly list-heavy but acceptable.

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 zero-parameter, read-only, closed-world list tool, the description is complete: it specifies what the fixed set is, enumerates the categories, and notes that each comes with a neutral description. No output schema exists, but the description gives the agent enough to know what to expect.

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 tool has zero parameters and the schema coverage is 100%, so there is no parameter meaning to add. The description correctly focuses on what the returned data represents rather than inputs.

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 name, title, and description together make it unambiguous: this tool returns the fixed set of delay cause categories. The description enumerates the exact categories, which also distinguishes it from sibling list tools like list_states and list_policies.

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 implies this is the reference for the closed taxonomy of structural bottleneck categories, so an agent can infer when to call it. However, it does not explicitly state when to choose this over siblings, mention prerequisites, or explain that it only provides static taxonomy rather than project-specific delay data.

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