x-mcp

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

With no annotations provided, the description carries full burden but lacks behavioral details. It doesn't disclose permissions needed, rate limits, whether replies are editable/deletable, character limits, or response format. 'Reply to' implies mutation but offers no safety or operational context.

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, efficient sentence with zero wasted words. It front-loads the core action and key parameters, making it easy to parse quickly.

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 mutation tool with no annotations and no output schema, the description is incomplete. It lacks critical context: authentication requirements, error conditions, return values, and how it differs from sibling tools like 'quote_tweet'. The 100% schema coverage helps but doesn't compensate for missing behavioral transparency.

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%, so parameters are fully documented in the schema. The description adds no additional meaning beyond implying 'tweet_id' and 'text' are required (matching schema), but doesn't explain parameter interactions or constraints like media attachment limits.

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 ('Reply to') and target resource ('an existing post on X'), distinguishing it from siblings like 'post_tweet' or 'quote_tweet'. However, it doesn't explicitly differentiate from 'reply_to_tweet' (itself) or mention alternatives like 'quote_tweet' for different reply types.

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 no guidance on when to use this tool versus alternatives like 'quote_tweet' or 'post_tweet', nor does it mention prerequisites (e.g., authentication, tweet visibility). It only states the basic action without context for selection.

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