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

Annotations already declare readOnlyHint=false, destructiveHint=true and idempotentHint=true, and the description is consistent with that: it discloses that names/headlines/colours are overwritten while 'the uploaded screenshots stay as they are'. It adds real context beyond the annotations by stating the return payload ('new previews and warnings'), that finish_project's open_url then opens the new version, and that edit_asset needs no sign-in (implying this path does). It stops short of stating auth or failure behaviour for this tool itself.

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?

Front-loaded with the core change operation before the alternative paths, and every sentence carries routing or behavioural information. The middle is dense with semicolons and slightly run-on, which costs a point but does not bury the actionable content.

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?

No output schema exists, and the description compensates by naming the return values (new previews and warnings) and their consumer (finish_project's open_url). Combined with the change scope, the unchanged-screenshots guarantee, and the full routing to edit_asset, an agent has everything needed to call it correctly in the project lifecycle.

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 100%, so the schema already documents device, screens, frame_color, background_color and project_handle with formats, lengths and examples. The description reinforces which fields are mutable and that only changed screens are sent, but adds no syntax or constraint beyond what the schema states. 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 specific verb and resource ('Changes a screenshot set create_project made') and pins the exact scope: screen name, headline, background colour, frame colour, device. It explicitly names the sibling it is not for ('For anything more ... use edit_asset') and distinguishes pre-save sets from already-saved ones, so an agent can separate it from edit_asset, create_project and finish_project without opening a schema.

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 when-to-use ('before the user saves it') and when-not-to-use, naming edit_asset as the alternative for extra changes, for a different canvas, and for sets the user already saved (by asset_id). It also states that once edit_asset has touched the set, the agent should stay with edit_asset. Nothing is left to inference.

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