Post Discussion Entry

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

The annotations already provide destructiveHint: true, indicating a write operation. The description adds the context that it is a 'reply,' which is useful. However, it does not disclose any other behaviors, such as permission requirements, whether the reply is immediately visible, or potential side effects. Given the annotations cover the destructive aspect, the description meets the minimum bar but does not enrich beyond that.

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 a single, focused sentence: 'Post a new entry (reply) to a discussion topic.' It is concise, front-loaded with the action, and contains no redundant phrasing or filler.

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 simple write operation with only three required parameters, all documented in the schema, and no output schema required, the description is nearly complete. It clearly states the purpose and is backed by strong schema coverage and annotations. The only minor gap is the lack of explicit mention that this operation requires an existing discussion topic or any caveats about message formatting, but these are implicit given the tool's name and parameter descriptions.

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 input schema already describes all three parameters (message, topic_id, course_id) with clear descriptions, achieving 100% coverage. The description does not add any additional meaning or usage context for the parameters. Since the schema carries the burden fully, the baseline score of 3 applies, and the description offers no extra value.

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 action: 'Post a new entry (reply) to a discussion topic.' It uses a specific verb and resource, and distinguishes this from sibling tools like create_discussion (which creates a topic) and update_discussion (which modifies one). The mention of 'reply' clarifies the specific operation intended.

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 implies usage: it is used to post a reply to a discussion topic. However, it does not explicitly advise when to use this over alternatives, such as create_discussion for new topics or list_discussions for browsing. It lacks explicit when-not-to-use guidance or comparison with related tools.

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