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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and non-destructive, so the description's job is to add context beyond those. It adds determinism ('Deterministic validation') and a concrete cost disclosure ('x402 price is $0.002 USD per call'), which are genuinely useful behavioral facts that annotations cannot express. No contradiction with the annotations.

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, each earning its place: purpose, usage guidance, and pricing, with the core validator behavior front-loaded. Slightly verbose boilerplate in the exclusion list and a minor grammar issue ('when validate that') keep it from a 5.

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 2-parameter tool with 0% schema coverage and no output schema, the description covers purpose, usage timing, safety (via annotations), and cost. However, it never describes what the validation result looks like (report? boolean? error list?) or the expected node/edge encoding, both of which an agent would need to invoke and interpret this tool correctly without further context.

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, and it only partially does. The workflow-graph framing and mentions of 'missing dependencies' and 'topological execution order' strongly imply that nodes are workflow steps and edges are dependencies, but the description never states the expected shape or encoding of either array (e.g., node identifiers, edge tuple format), leaving an agent to guess at invocation payloads.

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 first sentence names a specific verb (validation), resource (agent workflow graph), and enumerates exactly what it checks: cycles, missing dependencies, unreachable steps, and topological execution order. This cleanly distinguishes it from the sibling set, which contains execution-safety, reliability, and policy tools but no other workflow-dependency validator.

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 an explicit when-to-use trigger ('before spending money or causing side effects' when a multi-tool workflow must run in coherent dependency order) and a when-not-to-use exclusion for general knowledge and legal/identity/sanctions/fraud/contractual/regulatory matters. It stops short of a 5 because it names no alternative tool and the negative list reads as generic boilerplate rather than tool-specific guidance.

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