reply_to_thread

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

No annotations provided, so description carries full burden. It discloses that replies go through the original channel (email, Slack, chat), which is useful. However, it lacks details on idempotency, error handling, or whether the reply is visible immediately.

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?

Two sentences, no filler, front-loaded with purpose. 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?

For a simple send tool with no output schema, the description covers the core functionality and key parameters. It could mention whether the reply is visible to the customer, but that is implied. Adequate for the complexity.

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 coverage is 100% (all parameters described in schema). The description restates that textContent is required and markdownContent is optional, but adds no new meaning beyond the schema. Baseline 3 appropriate.

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 sends a reply to a customer thread, using the verb 'send' and resource 'reply to customer thread'. It also distinguishes itself from siblings like 'add_internal_note' by specifying the reply goes through the original channel.

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 mentions the reply is sent through the original channel, providing context. It implies this is for external customer replies, but does not explicitly exclude internal use (which a sibling tool 'add_internal_note' covers). No when-not-to-use guidance.

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