Cancel an open HyperLiquid order directly with your private key. Submit the asset symbol, order ID, and wallet private key to execute cancellation.
Cancel an open order directly with a private key on HyperLiquid.
| Name | Required | Description | Default |
|---|---|---|---|
| coin | Yes | Asset symbol | |
| orderId | Yes | Order ID (numeric) | |
| privateKey | Yes | Wallet private key (hex) |
Changes observed during successful MCP inspections.
v4.11.3Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It discloses that signing happens directly with a private key (a meaningful custody/auth detail), but says nothing about irreversibility, whether the order must still be open/fillable, error behavior for already-filled orders, or rate limits — all essential for a destructive mutation.
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 front-loaded sentence with no waste. It is arguably too terse for a destructive, key-handling operation, but on pure conciseness and structure it is efficient.
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 destructive, no-annotation tool that takes a raw private key and has no output schema, the description should cover safety, auth expectations, and what a successful/failed cancellation looks like. None of that is present, leaving significant gaps an agent must guess at.
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 100% (coin, orderId, privateKey all documented in the schema), so the baseline of 3 applies. The description adds no format, range, or domain detail beyond what the schema already provides.
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?
States a specific verb and resource ('Cancel an open order') plus the venue and signing method (HyperLiquid, private key). It does not distinguish itself from siblings like cancel_perp_order, cancel_all_perp_orders, hl_cancel_outcome_order, or update_order, so an agent cannot tell from the description alone which cancel variant applies.
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 versus the many cancel siblings or the managed/HL copy-trade cancel tools. 'Directly with a private key' hints at a self-custody signing path, but the description never states prerequisites or when this is preferred over cancel_perp_order.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.