reply_to_post

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

Description adds value beyond annotations by noting it creates a new post record, cannot be undone (delete_post as fallback), requires authentication, and is subject to rate limiting. No contradiction with annotations (destructiveHint false, idempotentHint false, openWorldHint true).

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?

Four sentences that are front-loaded with the core action and then provide alternatives, behavioral notes, and constraints. No wasted words; every sentence adds value.

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?

Given the tool's complexity (4 params, output schema), the description covers purpose, usage guidelines, behavioral traits, and parameter context adequately. Mentions rate limiting and undoability, leaving no critical gaps.

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?

While input schema covers all parameters with descriptions, the tool description adds semantic context for root and parent parameters (e.g., root must be original top-level post). Schema coverage is 100%, so baseline is 3; additional guidance justifies 4.

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 tool's purpose: replying to an existing post on AT Protocol with proper thread references. It uses specific verbs ('reply', 'creating') and distinguishes itself from siblings like create_post and create_thread.

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?

Explicitly states when to use this tool ('when the new content belongs inside an existing thread') and when to use alternatives ('use create_thread to start a multi-post thread from scratch'). Also mentions authentication requirements and that the action cannot be undone.

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