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

With no annotations provided, the description carries the full burden and does so well. It discloses the lesson is 're-injected at next voice mint', that content stays 'operator-authored' and doctrine is never invented, and details the write-tier approval workflow. This goes well beyond a basic write operation and helps the agent understand consequences.

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 two paragraphs, front-loaded with the core purpose, followed by usage, constraints, behavioral effects, and approval notes. Every sentence adds value and there is no wasted wording, though it is slightly longer than strictly necessary due to the approval paragraph. Overall well-structured.

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 write tool with no output schema and no annotations, the description is remarkably complete. It provides the action, when to use it, content limits, what happens to the data, and approval requirements. All necessary context for correct invocation is present, making it self-sufficient.

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 coverage is 100% with detailed parameter descriptions, so the baseline is 3. The description adds some context about lesson brevity and usage, but does not need to repeat what the schema already documents. It slightly reinforces the 'lesson' parameter semantics by saying 'what worked, what failed, which principle', but adds no new parameter-level details.

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 'Append one settleable CoS lesson for THIS operator only' — a specific verb, resource, and scope, which immediately distinguishes it from siblings like append_cos_preference and list_cos_lessons. It is a concise, action-oriented purpose statement.

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 says 'Use after a clear win/miss on a call' and specifies what to include ('what worked, what failed, which principle'), along with a constraint ('Short notes only — not transcripts'). It does not name alternatives or when-not scenarios, but the context is clear enough for an agent to decide appropriately.

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