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

Annotations already cover readOnly/idempotent/destructive, but the description adds substantial non-obvious behavior: 1-hour result caching with <5ms hits, failed calls never charged, and that exhaustion returns a payment-required quote rather than a fatal error, plus how to resume with agent_id or tx_hash. This is real operational context beyond the structured fields.

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?

The lead sentence is front-loaded and useful, but the body is bloated: the WHEN TO USE line restates the tool name and function tautologically ('when your task requires deterministic json-repair analysis for raw_json'), the payment flow repeats what the agent_id/tx_hash schema descriptions already say, and the trailing example adds nothing.

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?

An output schema exists so return values need not be explained, and the description still covers pricing, trial limits, caching, error-vs-quote behavior, and recovery steps. For a paid, cached repair utility nothing an agent needs to invoke it correctly is missing.

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%, so the baseline is 3, but the description adds meaning about parameter interaction: raw_json must be non-empty, and agent_id/tx_hash should be omitted during free trial calls or supplied for paid execution. That clarifies the intended sequencing of the three params beyond their individual schema docs.

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 (repairs) and resource (malformed/truncated LLM JSON) and enumerates concrete failure classes it handles: trailing commas, markdown fences, single quotes. An agent immediately knows what it does and can tell it apart from the wallet-status sibling.

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?

Explicit WHEN TO USE / WHEN NOT TO USE sections, and it names the alternative (get_agent_wallet_status) for quota checking. The exclusion ('unrelated domains or binary media') is fairly generic boilerplate rather than a precise boundary, so it falls just short of a 5.

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