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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, yet the description adds real behavioral context: server-side vs browser delegation, transient processing with no storage or logging, synthetic-inputs-only guidance, and an AP2 artifact with execution_hash for provenance. That is meaningful disclosure beyond annotations, though it omits error/failure behavior.

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?

It opens with a redundant pair ('M3P Monthly Cap Calculator: OpenChainGraph compute node... Deterministic OpenChainGraph compute node.') and spends much of its length on infra phrasing and FV-status receipt legalese with a raw URL. The genuinely useful sentences about execution and privacy are buried mid-paragraph.

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?

It covers compute binding, chaining, privacy, and the exported artifact despite having no output schema, but the core input — the field names inside policy_parameters — is pushed to 'the tool's manifest', so an agent still cannot form a valid decision-function call from the definition alone.

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 compute, parent_hashes, parent_tool_ids, and policy_parameters. The description only echoes the compute mode and hints at chaining via 'execution_hash for chain provenance', adding little beyond the schema; the required shape of policy_parameters is deferred to an external manifest.

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 restates the name and labels the node as 'payment_policy' but never explains what an M3P monthly cap is or what the tool actually computes. Its only elaboration is infrastructure boilerplate (compute modes, AP2 export), so an agent cannot distinguish this from dozens of sibling policy calculators beyond the title.

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?

It explains compute-mode selection ('auto' vs 'browser') but says nothing about when this M3P cap calculator should be chosen over the many overlapping payment-policy siblings. No prerequisites, exclusions, or alternative tools are named.

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