fxa_reply

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

With no annotations, the description carries the burden of disclosure. It provides useful context about the narrow side panel and the need for brevity, but omits potential side effects, prerequisites (e.g., whether a chart connection is required), or error behavior.

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 two sentences, front-loaded with the main action, and every clause adds meaning. It is concise and well-structured with no redundancy.

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 tool with a single string parameter and no output schema, the description covers the essential aspects: purpose, destination, and formatting constraints. It could mention what happens after sending, but this is not critical for such a straightforward operation.

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 already defines the 'text' parameter, but the description adds valuable guidance on the expected format (short and concrete) and the rendering context, which directly informs how the parameter should be populated.

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 the trader's chart panel. It uses the specific verb 'answer back' and identifies the destination, distinguishing it from sibling tools like fxa_connect_chart or fxa_wait_for_message.

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 the tool is for responding to the trader and explicitly instructs to keep the message short and concrete, with a note about the narrow panel. However, it does not explicitly mention when not to use it or name alternatives, though sibling context helps.

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