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

Goes well beyond the annotations (readOnly=false, destructive=false, openWorld=true) by disclosing that the reply is publicly visible to the entire course, that comments cannot be made private, that it reaches other people, that a per-call confirmation is on by default, and that a specific API key with app access is required. This is exactly the visibility/auth/confirmation context an agent needs for an outward-facing mutation.

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?

Purpose is front-loaded, but the text repeats itself: public visibility is stated twice ('public to the course' then 'the whole course sees the reply') and the confirmation requirement is stated twice ('By default you confirm each call' then 'confirm with the user before each call'). Trimming the redundancy would sharpen it.

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 public-impact mutation with no output schema, the description covers visibility, confirmation behavior, and auth requirements, so an agent can call it correctly. It stops short of anything on error behavior or limits, hence not a full 5.

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% with only two simple parameters (comment_id, body), so the schema already carries full parameter meaning. The description adds nothing beyond the schema, which is the baseline-3 case.

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 (reply to a lesson comment) plus the actor role (as the school owner), and clarifies the mechanism by comparing it to the Reply button in comment admin. It never names or contrasts a sibling such as teachable_moderate_comment, so the differentiation credit for a 5 is missing.

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?

Gives context (reply as the school owner) and prerequisites (Cotlet API key with app access), but offers no when-to-use vs when-not guidance and never points to an alternative tool. Usage is implied rather than stated.

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