lesson_append

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

The description claims the tool is idempotent ('repeated calls with the same title overwrite the existing section — idempotent'), but the annotation idempotentHint is false, creating a direct contradiction. Additionally, destructiveHint is false, yet overwriting content could be seen as destructive. No other behavioral details are provided.

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 bullet points for parameters and a clear main sentence. It is informative without excessive verbosity, though it could be slightly more compact. Each sentence contributes value.

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 primary behavior and parameter semantics but omits details such as success/failure responses or error conditions. Given the presence of an output schema (not shown), return values may be partially covered. However, the contradiction and lack of usage guidelines leave gaps.

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?

With 0% schema description coverage, the description fully explains each parameter: title is sluggified to a key, body goes verbatim, summary is an optional blockquote, source is a provenance tag. This adds essential meaning beyond the schema's simple type and default.

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: 'Materialize a class-level lesson into ~/.threadkeeper/lessons.md.' It explains the idempotent overwrite behavior, which distinguishes it from sibling lesson tools like lesson_remove (removal) and lesson_get (retrieval). The verb 'append' is appropriate as it adds a section, but idempotency is highlighted.

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?

Usage is implied by the description (recording lessons), but there is no explicit guidance on when to use this tool versus alternatives like lesson_list or lesson_remove. No exclusions or specific context are provided.

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