get_order_book

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

Beyond the readOnlyHint annotation, the description discloses that snapshots are periodic rather than per-tick, and details the output structure including time, price, bucketWidth, and bucket percentages. This adds meaningful behavioral context without contradicting the annotation.

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 concise yet comprehensive, with a clear opening statement followed by structured details. Every sentence contributes useful information about behavior or output format, with no redundant phrases.

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?

The description adequately covers the tool's purpose, output format, and key behavioral nuances. While it doesn't address alternative tools or error scenarios, the presence of an output schema and read-only annotation reduces the burden, making it reasonably complete.

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 100%, so the schema already documents all parameters thoroughly. The description adds minimal new parameter insight—it mentions depth trimming and snapshot time but largely mirrors the schema's existing descriptions.

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 'Fetch the aggregate pending-order book for an instrument,' clearly identifying the verb, resource, and scope. It distinguishes itself from sibling tools like get_position_book by specifying 'pending-order book' and 'aggregate'.

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 description does not explicitly state when to use this tool over alternatives such as get_position_book or get_candles. It implies the use case via the title and first sentence but lacks direct comparison or exclusion statements, so it falls at the 'implied usage' level.

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