message_agent

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

Annotations already mark readOnlyHint=false and destructiveHint=false, indicating a write operation without destructiveness. The description adds behavioral context beyond annotations by specifying that the message is 'persisted' and that 'delivery continues the recipient's conversation and records the reply,' which clarifies the side effects on the conversation history.

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 with no fluff, front-loading the primary action and outcome. Every clause adds relevant information, making it concise and well-structured.

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?

While the core purpose is clear, the description omits essential details for correct invocation: parameter semantics (especially the optional from_agent_id), expected response format, and any prerequisites or error conditions. Given there is no output schema, the lack of return-value description is a notable gap.

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 0%, so the description carries the full burden of explaining parameters. It only hints at the from/to relationship ('from Codex or one team member to another') but does not explicitly map to the four parameters (message, team_id, to_agent_id, from_agent_id). No parameter-specific meaning is added, leaving agents to infer from parameter names alone.

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 ('Send a persisted message'), the participants ('from Codex or one team member to another'), and the effect ('continues the recipient's Antigravity conversation and records the reply'). This is a specific verb+resource and distinguishes it from sibling tools that handle media generation, runs, or teams.

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 inter-agent messaging within the Antigravity platform, but it does not explicitly state when to use it over alternatives or when not to use it. No exclusions or comparisons to siblings are provided, leaving the context implicit.

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