send_sender_action

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

With no annotations, the description carries the full behavioral burden and does not disclose that these actions are ephemeral state signals rather than messages, nor any permission, rate-limit, or persistence details. It essentially restates the enum values from the schema.

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?

A single well-formed sentence that front-loads the purpose and enumerates the actions. No filler, though it could have used a second sentence for behavioral context rather than none.

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 zero-annotation, no-output-schema tool, the description explains only the action names. It omits whether a message must be sent, session/permission requirements, and what happens on success or failure, leaving real 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?

Schema coverage is 100%, so the schema already documents recipient_id and action. The description adds minor value by mapping 'typing_on'/'typing_off' to a typing indicator and 'mark_seen' to a read receipt, but offers no format or constraint detail beyond that.

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?

States a specific verb (trigger) and resource (sender actions in Instagram chat), and enumerates the three supported actions. This lets an agent distinguish it from message-sending siblings like send_instagram_dm, though it does not explicitly name any sibling.

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 phrase 'in Instagram chat' implies the operational context (an existing conversation), but there is no explicit guidance on when to prefer this over send_instagram_dm or reply tools. The enum values make the intent reasonably inferable.

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