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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), yet the description goes well beyond them: 1-hour caching with <5ms hits, $0.01 per call, 5 free calls per agent_id, failed calls never charged, and the non-fatal payment-required quote with a $2 top-up link and USDC addresses. This is the kind of operational context an agent needs to plan a call and handle the quota response correctly.

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?

Purpose is front-loaded and the WHEN TO USE / WHEN NOT TO USE / PARAMETER INTERACTIONS headers make it skimmable. It is dense and mildly repetitive on pricing (free-trial terms are restated across several sentences), which costs a point but not legibility.

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. Given a metered, payment-gated tool, the description still covers the full lifecycle: trial, cache behavior, payment-required response, and retry path with agent_id or tx_hash. Nothing an agent needs to invoke or recover from this call 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 schema already defines each parameter; the baseline would be 3. The description adds value the schema cannot: the trial-vs-paid orchestration rule (omit agent_id/tx_hash for the free calls, pass agd_pass_ or tx_hash for paid execution), which governs how the parameters are combined rather than what each one means.

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 (fetches) and resource (live Polymarket prediction market orderbooks, implied Yes/No probabilities, volume, whale sentiment) scoped to macro/crypto/AI events. It also names the only sibling, get_agent_wallet_status, and distinguishes its role, so an agent can tell the two apart without opening schemas.

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 and WHEN NOT TO USE sections, plus a named alternative (get_agent_wallet_status for quota/balance) and the condition that selects it. The tool's own trigger condition (deterministic polymarket-odds analysis for `topic`) is spelled out rather than implied.

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