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

With no annotations, the description carries the full burden and does disclose two important traits: output ordering ('normalized oldest-first candles') and a payment requirement ('Costs $0.005 USDC on Base via x402'). It omits pagination, rate-limit, and retry behavior, but the cost and ordering disclosures are genuinely valuable.

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?

Two tight sentences, front-loading the resource and output shape, then the cost. No wasted words; every clause carries information.

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 3-param tool with no output schema and no annotations, the description covers output ordering and cost but leaves return-value detail shallow and the under-documented 'since'/'interval' parameters unexplained. Adequate but with clear gaps.

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 only 33%, so the description needs to compensate but instead just restates the parameter names ('symbol, interval and optional since'). It adds no meaning for 'interval' allowed values, 'since' format, or symbol syntax beyond what the schema already implies.

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+resource ('crypto OHLCV series' producing 'normalized oldest-first candles'), which is clearer than the opaque tool name. However, it never distinguishes itself from the sibling crypto-candles, which appears to cover the same resource, so an agent cannot confidently route between them.

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?

'For recurring market-data workflows' gestures at context but gives no when-to-use-vs-alternatives guidance, and no exclusion logic against the overlapping crypto-candles or canonical-crypto-spot-price siblings. The agent is left to infer selection on its own.

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