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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the description doesn't need to repeat those. It adds valuable context beyond annotations: it notes the tool is 'read-only, idempotent' (matching annotations), details auth requirements (Bearer <token> any plan), explains that state changes only when evidence is added, and describes the output structure. This is slightly above the baseline 3 because it provides operational context like rate-of-change and output details.

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 with clear sections: a behavior summary, explicit WHEN TO CALL / WHEN NOT TO CALL, and a BEHAVIOR section. It's information-dense but each sentence adds value—no fluff or repetition. The description front-loads the core purpose and then provides usage boundaries, making it scannable for an agent.

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?

Given the tool has 0 parametersasi and an output schema that likely describes the structure, the description is complete. It covers purpose, usage, when-not-to-call, auth, and the required output fields (thin_stages, missing principles, evidence_count, coaching_note). It also links to related tools. No critical gaps remain for an agent to call it correctly.

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 0 parameters, and schema description coverage is 100% (trivially, since no properties). The description appropriately states 'Authenticated' and mentions the auth token, which is the only input consideration. With no parameters to describe, the baseline is 4, and the description doesn't need to add parameter semantics but does clarify auth context.

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 purpose: returning stages in the caller's active course with thin recorded evidence, including missing principle slugs and diagnostics. This is specific with a verb ('returns') and resource ('stages in the caller's active course'), and it distinguishes itself from siblings like me.learning_path or me.validation_history by focusing on evidence gaps.

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 explicitly states when to call: when the user asks 'what should I work on next' or 'what's weak in my Blueprint progress'; and when not to call: to lecture on already satisfied principles or on every conversation turn. It also mentions pairing with me.add_evidence to close gaps, providing clear routing among siblings.

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