Get the per-UC usecase diagram

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

With no annotations provided, the description carries the full behavioral burden and does so richly: read-only, path-safety-guarded id that raises ValueError before any file access, cache-aware reads, parse failures returning a non-raising ParseFailureResult with error/path/id, and a raised not-found error for truly absent ids. This is far more than the annotations would have supplied and covers failure modes, safety, and caching explicitly.

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 purpose and scope are front-loaded in the first sentence and every clause conveys substantive information. It is dense with parenthetical references (specmgr://uc/plantuml §2.5, feat-150 precedent) that assume internal context, keeping it short of a clean 5 but without wasted filler.

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-param read tool with an output schema, the description covers everything needed: what it returns (PlantUML source, explicitly not a specmgr document), the guarded id contract, cache behavior, and both failure-mode outcomes. Nothing an agent needs to call it correctly is missing.

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?

There is one parameter (id) at 0% schema coverage, but the description compensates by explaining that the id is path-safety-guarded and that a wrong-format id raises a ValueError before any file access. That adds real meaning about format expectations and failure behavior beyond the bare 'string' 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 (render/return), resource (PlantUML usecase diagram), and scope (for one use case), which cleanly distinguishes it from siblings like get_use_case_package_diagram and get_uc_sequence_skeleton. An agent can tell exactly what artifact this produces without opening the schema.

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?

Gives a clear follow-up path by directing the agent to run the output through validate_plantuml for a validation verdict, which is genuine when-to-use-next guidance. However it never explicitly contrasts this tool against the sibling diagram/example tools (e.g., get_use_case_package_diagram or get_uc_plantuml_template), so the alternative-selection guidance is implied rather than stated.

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