Cancel or replace existing trading orders using FIX protocol messages (35=F or 35=G) to modify order parameters like quantity, price, or symbol.
Cancel or replace an existing order via FIX 35=F or 35=G.
| Name | Required | Description | Default |
|---|---|---|---|
| order_id | Yes | ||
| action | Yes | ||
| new_venue | No | ||
| new_quantity | No | ||
| new_price | No | ||
| new_symbol | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations are absent, so the description must disclose behavioral traits. It mentions FIX message types but omits safety, destructive nature, and side effects. The agent cannot infer if the operation is idempotent or has prerequisites.
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?
A single sentence efficiently conveys the core purpose and technical detail (FIX message types). It is front-loaded and easy to parse, though it sacrifices completeness.
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 6 parameters, no output schema, and no annotations, the description is insufficient. It fails to explain return values, conditional behavior, or the relationship between action and new_* fields.
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 0%, so the description must explain all parameters. It only hints at order_id and action (cancel/replace) but ignores new_venue, new_quantity, new_price, and new_symbol, leaving their purpose entirely unclear.
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 cancels or replaces an order, using specific FIX message types. It distinguishes from sibling tools like cancel_algo (which cancels algo orders) and send_order (which sends new orders).
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 on when to use this tool versus alternatives. With siblings like cancel_algo and modify_algo, the description should explicitly mention when to pick this tool (e.g., for manual FIX-based cancellation/replacement) but does not.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.