get_ohlcv

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

With no annotations, the description carries the full burden, and it does well: it discloses the DuckDB cache-first behavior, REST topping-up of the tail, the acceptable timeframe formats, and the limit cap of 1000. It omits details like error behavior or pagination, but for a read-only OHLCV tool, this is solid transparency.

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 description is compact: two sentences plus a parenthetical. The main purpose is front-loaded, and each clause provides actionable detail (caching, formats, cap) without fluff. No wasted words.

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?

Given the presence of an output schema, no return-value explanation is needed. The description covers caching architecture, input formats, and limits, which is adequate for a data-fetching tool. It could mention exchange behavior or symbol validation, but these are minor gaps for the tool's complexity.

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 0%, so the description compensates by explaining timeframe ('1m,5m,15m,1h,4h,1d'), since (ISO-8601 or epoch-ms), and limit (capped at 1000). It does not explain symbol or exchange, but those are self-explanatory. This adds meaningful semantics beyond the bare schema.

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 opens with 'Get historical OHLCV candles,' which is a specific verb-resource pairing that clearly differentiates it from siblings like get_ticker (current price) and get_recent_trades (trades). The phrase 'basis for charts and indicators' further clarifies the domain and intended use.

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 provides context by mentioning it serves historical candles for charts/indicators, implying when to use it over ticker/trade tools. However, it does not explicitly state 'use this instead of X' or list when-not-to-use scenarios. This is clear context but not full exclusionary guidance.

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