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

With no annotations, the description discloses key behaviors: returns a markdown table, caps at 30 rows, adds truncation footnote. This provides substantial transparency beyond the input schema, though it omits any reference to authentication or billing requirements (handled via npub parameter).

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 concise sentences. The first states the core purpose, the second explains the output format and truncation behavior. 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 (handling return values), the description covers purpose, output format, and a behavioral trait (truncation). It does not explain period-frequency combinations or usage context, but it is largely complete for a data retrieval tool.

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 description coverage is 86% (high), so baseline is 3. The description adds no parameter-level details beyond the schema; it does not explain valid period-frequency combinations or the meaning of the 'npub' parameter beyond what is already in the 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?

Explicitly states 'Get historical OHLCV candle data for a symbol', clearly specifying the verb (get) and resource (historical candle data). This distinguishes it from related tools like schwab_check_price which gives current price.

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?

Implied usage for historical data but no explicit when/not-to-use guidance or mention of alternatives. The description could be improved by noting when to prefer this over schwab_check_price or other market data tools.

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