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

Goes well beyond readOnlyHint/openWorldHint by disclosing the paid-access model (3 free calls/day across all tools, then $0.005 USDC via x402 or card credits paid in-band through params._meta['x402/payment']), the upstream data source (GeckoTerminal public DEX API, 8 chains), and a 'not financial advice' caveat. It omits pagination/truncation behavior and what happens if no liquid pool exists, which are the remaining behavioral gaps.

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?

Every sentence carries information and the pricing disclosure is compact given its complexity. The structure is slightly off, though: the long billing/x402 sentence occupies the prime front-loaded position, pushing the actual purpose ('Token price history: OHLCV candles…') into the second slot.

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?

With annotations covering the safety profile, an output schema covering return values, and 100% param coverage, the remaining burden is payment mechanics and data provenance, both of which are addressed. Only minor gaps remain (behavior when no pool exists, candle truncation), which are low-impact for correct invocation.

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 already 100%, so the baseline is 3, and the description adds real value by stating the hard ceilings the schema omits: limit maxes of 180 (day) and 168 (hour), versus the schema's defaults of 30/48. It also clarifies that candles come from the token's most liquid pool, explaining how address/network are resolved.

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 resource (OHLCV candles) with concrete scope: daily up to 180 or hourly up to 168 candles for a single DEX token, sourced from its most liquid pool, including period change/high/low. That implicitly separates it from spot-price siblings like token_price/token_prices, but the description never names those siblings to make the split explicit.

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 'When to use' sentence exists but largely restates the purpose line ('daily or hourly OHLCV candles of a DEX token') rather than giving conditions or exclusions. No alternative sibling is named, and there is no guidance on when to prefer token_price/token_prices or token_compare instead.

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