Reply to Code Discussion

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

With no annotations, the description carries the full burden. It discloses the action, notes that Markdown is supported, and explains where to find the channel ID. However, it does not mention side effects (e.g., who gets notified, whether replies can be edited/deleted) or any permission requirements. This is acceptable for a straightforward mutation tool but not deeply transparent.

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 concise and well-structured: a single sentence stating the core action, a helpful note about finding the channel ID, then an Args list and Returns line. Every sentence provides value, with no redundant or vague language.

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 reply tool, the description covers the essential elements: purpose, parameter semantics, how to obtain a key identifier, and the return type (confirmation message, with an output schema available). Missing items like error scenarios and explicit alternatives to sibling tools are minor gaps, so this is close to complete but not fully so.

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 schema provides only names and string types (0% coverage), but the description adds crucial meanings: project is 'Project key', review_id is 'MR number', discussion_channel_id is the 'Channel ID of the code discussion', and text is 'Reply text'. It also clarifies that project/review_id are 'for context only' and that Markdown is supported. This meaningfully compensates for the bare schema, though the phrase 'for context only' could be clearer.

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 with a specific verb and resource: 'Reply to an existing code discussion on a merge request.' It uses 'existing' to distinguish from creating a discussion, and the sibling tools (post_code_discussion) reinforce this distinction, making the purpose unambiguous.

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 provides clear context on when to use the tool (to reply to an existing discussion) and gives a specific source for the discussion_channel_id (timeline output). However, it does not explicitly mention alternatives or exclusions (e.g., use post_code_discussion to start a new discussion), so it falls just short of full guidance.

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