Talk to the Google Flow agent

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

With no annotations, the description carries the full burden and does well: it discloses that the call blocks until the reply completes, that sending does not spend credits, that a pendingApproval with quoted cost halts progress, and that images are typically produced immediately. It leaves out error/timeout behavior and session-memory implications, which are only partly covered by the new_session parameter.

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?

It is dense but front-loaded: the core action and return shape come first, then the approval branch, then the media branch. A couple of clauses run long, but almost every sentence carries actionable information.

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 10-parameter tool with no output schema, the description explains the important return keys (messages, reply, media, pendingApproval) and the key branch decisions. It stops short of describing less common outcomes or the effect of new_session on conversation state.

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 90%, so the schema already explains message, media_ids, characters, attachments, confirm_rights, etc. The description adds behavioral meaning for the approval and media-id outcomes rather than new parameter detail, so the baseline 3 applies.

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 concrete verb and resource (send one message to the Flow agent, return when the reply completes) and names the returned fields. It is clearly distinguishable from siblings such as flow_approve and flow_wait, which it explicitly references.

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?

Gives explicit routing: if pendingApproval appears, tell the user the cost and call flow_approve; download media via flow_wait; answer questions or refine in a follow-up send. It also tells the agent that sending itself never spends credits, which informs when it is safe to call.

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