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

Annotations already flag destructiveHint=true and idempotentHint=true; the description adds valuable specifics beyond them: occupied scene numbers are preserved unless replaceExisting is true and the user requested replacement, and identical retries return the saved scene. It does not state auth requirements, but the mutation semantics are well disclosed.

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?

Three sentences, no filler, with the approval constraint front-loaded and the replaceExisting behavior immediately after. Every sentence carries distinct, load-bearing 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 mutation tool with an output schema, the description covers the key behavioral risks (accidental overwrite, unapproved drafts, retry behavior). The remaining gap is undocumented parameters like title and continuityNotes, but the core invocation semantics are complete.

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% across 6 params, but the description clarifies the most consequential one, replaceExisting, including the prerequisite that the user must have requested replacement. It says nothing about title, projectId, or continuityNotes, leaving half the parameters undocumented.

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: 'Store a concise summary of a scene the user has approved.' An agent can distinguish this write tool from the read-only sibling list_approved_scenes, though no sibling is named explicitly.

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?

Provides a clear negative condition ('Never record an unapproved draft') and a conditional for replacement, which gives real when-to-use guidance. It does not name alternatives such as list_approved_scenes, so it stops short of full routing guidance.

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