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

Annotations already mark the tool as read-only and non-destructive. The description adds valuable behavioral context beyond the annotations: it returns markdown, must be called after get_context, and enforces path constraints ('relative, end in .md, and cannot traverse (..)'). It doesn't detail error behavior or auth requirements, but the safety profile is already covered by annotations.

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 well-structured, starting with purpose and timing, then offering examples. The numbered input options and bulleted examples improve scannability. It is somewhat repetitive (the same skill IDs appear in the prose and examples), but the extra length is justified by the tool's need to disambiguate between two input modes.

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?

The description covers the core contextual needs: what the tool loads, the return format (markdown), sequencing relative to get_context, the two accepted input forms, and path constraints. For a read-only, single-parameter tool with no output schema, this is largely sufficient. It stops short of explaining failure modes or listing all possible skill IDs, but those are discoverable via list_skills.

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?

Although schema coverage is 100%, the description adds substantial meaning beyond the schema: it maps user intents to concrete skillId values, provides representative examples for both catalog IDs and repo-relative paths, and introduces path validation rules not present in the schema. This exceeds the baseline expected for fully covered schemas.

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 clearly states the tool's action: 'Load a workflow guide or any markdown file from the Costory skills GitHub repo' and notes it 'Returns markdown.' It distinguishes itself from siblings by specifying its timing ('call BEFORE starting the task, AFTER get_context') and by saying 'Call this instead of guessing the tool sequence.'

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 explicit guidance on when to use the tool: before starting a task, after get_context, and for build tasks it recommends specific mechanics skills. It also explains the recipe workflow and the two valid input forms. However, it doesn't explicitly state when not to use the tool versus alternatives like get_documentation_page, so it falls short of full exclusionary guidance.

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