Replace Order

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

Annotations already indicate destructiveHint=true and readOnlyHint=false, so the description doesn't need to restate mutation. It adds the condition that only open/pending orders are modifiable, which is useful behavioral context beyond the annotations.

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 sentences: the first defines the action and target, the second adds a usage condition. No wasted words, front-loaded with the core purpose.

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 annotations and full schema, the description is sufficiently complete. It communicates the success return message and the constraint on order status. The only minor gap is not mentioning error behavior for non-open orders, but that can be inferred.

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?

With 100% schema coverage, the schema already defines all parameters. The description lists a subset of parameters (quantity, price, trigger_price, trailing params) but adds no new details beyond what the schema provides, leaving the agent to rely on the schema for semantics.

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 'Modify an open order's quantity, price, trigger_price, or trailing params.' It uses a specific verb ('Modify') and identifies the resource ('open order'), distinguishing it from siblings like submit_order or cancel_order.

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 includes the condition 'Only open/pending orders can be modified,' providing clear context on when to use this tool. It does not explicitly mention alternatives like cancel-and-resubmit, but the condition is sufficient for guidance.

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