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

The description goes beyond the annotations: it explains the non-idempotent behavior concretely ('saving the same generation twice makes two frames, so do not retry a call that may have gone through'), the privacy default ('private to the account unless explicitly asked to share'), and the lifecycle limitation (no edit/delete tool). Annotations already flag idempotentHint=false, but the description adds actionable consequences.

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?

Four sentences, each carrying essential information. The core action is front-loaded, the critical warning about duplicate saves is placed early, and the final sentence addresses scope boundaries. No filler or 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 creation tool with an output schema, the description is complete: it covers side effects, privacy, booth assignment, non-idempotency, and the absence of edit/delete tools. An agent has all the context needed to invoke correctly and set expectations.

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 baseline is 3. The description adds provenance beyond the schema: it tells the agent that threadId and generationId come from check_generation, and that name should use the operator's words if provided. This connects parameters to the workflow, which is meaningful additional semantics.

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 states a specific verb and resource: 'save one generation... as a real frame in this operator's frame list, with its photo windows cut out.' It clearly differentiates from siblings like check_generation, refine_frame, and start_frame by naming the exact output and context. An agent can tell this is the frame-creation step, not a preview or edit.

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?

Explicitly says 'Call it only when the operator has chosen a result' and instructs to pass the threadId and generationId returned by check_generation. It also states what this tool does not do: it does not assign the frame to a booth, and no tool edits or deletes frames. This gives clear when-to-use and 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.