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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint=false, so the safety profile is covered. The description adds genuine operational context beyond that: the argument provenance (paths must come from popcraft_get_workflow_instructions) and the gating condition. It does not describe error behavior for invalid paths, which keeps it short of a 5.

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 tight sentences, front-loaded with verb+resource, followed by the gating rule and a concrete call example. The trailing API docs URL is mildly extraneous but plausibly useful, keeping it just under a perfect score.

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 two-parameter, fully-documented, annotation-covered read tool with no output schema, the description supplies purpose, provenance, gating, and an example. What a reference file returns is not spelled out, but that gap is minor given the richness of the surrounding structured data.

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 description coverage is 100% and both parameter descriptions already carry format and examples ('references/board-design.md', 'ugc-ad'). The description's inline example largely repeats that, adding little beyond the schema, so baseline 3 is appropriate.

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 and resource (read one bundled reference file from a Popcraft workflow) and immediately ties it to the sibling popcraft_get_workflow_instructions as the source of paths. An agent can distinguish this from the workflow-instructions and generation tools without opening any 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?

Explicitly states when to call it ('when the loaded workflow instructions tell you to load a reference module') and names the alternative/source tool that supplies the arguments. The condition that selects this tool is unambiguous.

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