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

Beyond the annotations (write, idempotent, non-destructive), it discloses required scopes (media:read+media:write+generations:write and active grant), the deterministic/idempotent nature of publishing, and what it explicitly does NOT do (no downstream connection, no paid generation). This is exactly the extra behavioral context an agent needs for a write op.

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?

Two tightly packed sentences, front-loaded with 'Explicit owned-media WRITE,' and no wasted clauses. The critical write-scope and exclusions are surfaced immediately.

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 mutation tool with no output schema it covers permissions, side effects, and exclusions well. The gaps are the undocumented parameter semantics (especially result_index) and no explicit statement of what is returned, though 'publish a durable PNG' implies the outcome.

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 must compensate. It implies project_id/scene_id via 'saved storyboard' and 'one FINISHED scene' and gestures at result_index via 'selected result,' but it never explicitly specifies which result is chosen when result_index is omitted or the semantics of that parameter. It partially compensates but leaves real gaps.

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 and resource: 'deterministically publish a durable, last-decoded PNG from the selected result of one FINISHED scene in your saved storyboard.' It also distinguishes itself from siblings by ruling out connecting a downstream scene and starting paid generation, so an agent can separate it from attach_scene_continuation/start_execution without opening schemas.

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 clear context (a FINISHED scene in a saved storyboard) and explicit exclusions ('never connects a downstream scene or starts paid generation'). It does not name the specific alternative sibling tools, so the routing is implied rather than fully spelled out.

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