---
title: "Approve Hyperliquid builder-code fee cap for an agent"
method: POST
path: "/trade/{venue}/approve-builder"
tags: ["Trading"]
---

# Approve Hyperliquid builder-code fee cap for an agent

`POST /trade/{venue}/approve-builder`

Operator recovery endpoint. Auth deliberately accepts platform operators or tenant admins and must not require an agent JWT, so humans can recover funds when the agent token is expired. Raw signing keys never leave the vault; all recovery actions are audited and idempotency-protected. Platform-key only route that submits Hyperliquid's user-signed approveBuilderFee action. The approval must be signed by the agent's master Hyperliquid wallet, not an API/agent wallet.

## Headers

- `X-Steward-Request-Timestamp` string
- `X-Steward-Request-Expires-At` string
- `X-Steward-Signature` string
- `X-Steward-Signing-Key-Id` string
- `Idempotency-Key` string

## Request body

- object
  - `agentId` string, required
  - `idempotencyKey` string
  - `builder` string, required
  - `maxFeeRate` string, required

## Response `200`

JSON response

- object
  - `ok` true, required
  - `data` object, required
    - `venue` 'hyperliquid'
    - `walletAddress` string
    - `builder` string
    - `maxFeeRate` string
    - `result` object

## Other responses

- `400` — JSON response
- `401` — JSON response
- `403` — JSON response
- `404` — JSON response
- `408` — JSON response
- `409` — JSON response
- `502` — JSON response

## Changes

- **2026-08-17** `261a7c8070b2` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/steward-fi/apis/steward-api/changes/trade/:venue/approve-builder/post.md)

---

[API](https://skmtc.dev/steward-fi/apis/steward-api.md) · [All operations](https://skmtc.dev/steward-fi/apis/steward-api/llms.txt) · [OpenAPI document](https://skmtc.dev/steward-fi/apis/steward-api/revisions/b88b4b97a664?raw)