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

The description explains behavior annotations cannot: calling again yields a fresh link and retires the previous one, which directly accounts for idempotentHint=false and destructiveHint=true. It stops short of describing auth requirements, failure behavior on invalid files, or rate limits.

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 tight sentences: the validation behavior is front-loaded, followed by the link lifecycle. Every clause earns its place, and the re-call/retirement caveat is genuinely load-bearing rather than filler.

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?

With no output schema, the description correctly explains the return value (the editor link) and its lifecycle. It covers validation, return, and non-idempotency well, but omits what happens when validation fails, which an agent calling a checker would want to know.

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% and the single project_handle parameter is fully documented there (including that create_project returned it), so the description adds no parameter detail. Baseline 3 is appropriate when the schema carries the parameter burden.

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 specific verbs and resources: it validates that every project screenshot was uploaded and is a real PNG/JPEG, then returns an editor link. This is clearly distinct from siblings like make_screenshot_set or save_to_account, though it never names those siblings to sharpen the contrast.

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?

Usage is only implied – an agent infers this is the finalization step after uploading screenshots, and that the returned link is then saved via save_to_account, but no explicit when-to-use or when-not-to-use guidance or alternative routing is given.

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