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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the safety profile is partly covered; the description usefully adds that nothing is submitted and that request_id can be replayed. There is a mild tension with idempotentHint=false, since replaying a request_id to 'recover the same prepared request' sounds idempotent, but 'current price' plausibly changes, so it is not a hard contradiction. It says nothing about what validation can fail on or what happens on a revision conflict.

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 short sentences, each earning its place: purpose first, then the crucial non-submission boundary, then the request_id replay note. Zero 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?

For a four-parameter, no-output-schema, state-touching tool, the description leaves expected_rev and node_ids semantics entirely unexplained and does not say what the 'input summary' contains or what validation failures look like. It covers the return value at a high level but not enough for an agent to call it correctly on the first try.

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 four required parameters, and the description explains only request_id (replay semantics). expected_rev is presumably an optimistic-concurrency guard, node_ids has cardinality limits, and project_id scope is unstated — none of that is explained anywhere.

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 ('Validate selected configured Canvas generation nodes') plus the return payload ('current price/input summary'), and explicitly bounds the scope with 'This does not submit generation'. It stops short of naming the sibling it contrasts with (aimixer_canvas_start_execution), so an agent must infer the pairing, but the boundary is unambiguous.

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?

The negative guidance ('does not submit generation') plus the request_id replay note ('Reuse request_id to recover the same prepared request') gives an agent a clear operating context: call this to preview/validate, then submit elsewhere. No explicit when-not exclusions or named alternatives, which keeps it below a 5.

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