crypto_get_previous_close

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

With no annotations, the description carries the full burden of behavioral disclosure. It only states the core action but does not mention return format, data availability, adjustment behavior, rate limits, or any caveats. For a simple read operation this might be acceptable, but it adds no behavioral context beyond the function name.

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 a single, front-loaded sentence that immediately conveys the essential action. It is appropriately concise for a tool with only two parameters and no detailed return structure, containing no redundant or filler content.

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 tool with no annotations, no output schema, and low schema coverage, the description is too minimal. It does not specify what 'previous day' means in terms of trading days, how 'adjusted' affects the OHLC values, or what response to expect. The agent has insufficient information to correctly invoke the tool with confidence.

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?

The schema has 0% description coverage, so the description must compensate. It only hints that 'symbol' refers to a 'crypto pair' but gives no format or examples (e.g., BTCUSD). The 'adjusted' parameter is entirely unexplained—its purpose, default behavior, and impact on the result are omitted.

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 clearly states the tool's function: 'Get previous day's OHLC for a crypto pair.' It uses a specific verb ('Get'), identifies the resource ('previous day's OHLC'), and scopes it to 'crypto pair,' which distinguishes it from sibling tools like stocks_get_previous_close and forex_get_previous_close.

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?

No guidance is provided on when to use this tool versus alternatives such as crypto_get_daily_open_close or crypto_get_aggregate_bars. There are no exclusions, prerequisites, or explicitly named alternatives, leaving the agent to infer usage from the name alone.

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