From fda1e9d9fe593de45d4f77d52ed21de11fdc673c Mon Sep 17 00:00:00 2001
From: "Ian C." <ian@0xmonaco.com>
Date: Wed, 22 Apr 2026 11:37:28 +0100
Subject: [PATCH 1/2] Align close position with REST path contract

The close-position endpoint identifies the position in the URL path. Sending position_id again in the JSON body now fails against the backend's deny-unknown-fields request schema, so the SDK only sends close parameters in the body.

Constraint: Backend expects /api/v1/positions/{position_id}/close with close_type payload only

Rejected: Loosen backend JSON parsing | would hide stale client contracts instead of fixing SDK request shape

Confidence: high

Scope-risk: narrow

Directive: Keep resource IDs in path-only bodies out of SDK JSON payloads unless the backend contract explicitly requires duplication

Tested: bun test packages/core/tests/unit/api/positions.test.ts; bun run check
---
 packages/core/src/api/positions/api.ts         | 1 -
 packages/core/tests/unit/api/positions.test.ts | 1 -
 2 files changed, 2 deletions(-)

diff --git a/packages/core/src/api/positions/api.ts b/packages/core/src/api/positions/api.ts
index 4677947e..e1b6a8b7 100644
--- a/packages/core/src/api/positions/api.ts
+++ b/packages/core/src/api/positions/api.ts
@@ -46,7 +46,6 @@ export class PositionsAPIImpl extends BaseAPI implements PositionsAPI {
     return await this.makeAuthenticatedRequest<ClosePositionResponse>(perpRoutes.positions.close(positionId), {
       method: "POST",
       body: JSON.stringify({
-        position_id: positionId,
         close_type: request.closeType,
         limit_price: request.limitPrice,
         slippage_tolerance_bps: request.slippageToleranceBps,
diff --git a/packages/core/tests/unit/api/positions.test.ts b/packages/core/tests/unit/api/positions.test.ts
index 4cfa874c..fe7db42e 100644
--- a/packages/core/tests/unit/api/positions.test.ts
+++ b/packages/core/tests/unit/api/positions.test.ts
@@ -87,7 +87,6 @@ describe("PositionsAPIImpl", () => {
         Authorization: `Bearer ${mockAccessToken}`,
       },
       body: JSON.stringify({
-        position_id: positionId,
         close_type: "LIMIT",
         limit_price: "50500",
         slippage_tolerance_bps: 100,

From 1fd5d17f498c6bf9bcdf46028e20c42b3243dce4 Mon Sep 17 00:00:00 2001
From: "Ian C." <ian@0xmonaco.com>
Date: Wed, 22 Apr 2026 23:53:03 +0100
Subject: [PATCH 2/2] Release close-position contract fix

The close-position SDK fix changes the published @0xmonaco/core package behavior, so it needs a patch changeset for the release pipeline.

Constraint: Changesets bot requires package-impact metadata for SDK release PRs
Confidence: high
Scope-risk: narrow
Tested: bun test packages/core/tests/unit/api/positions.test.ts
Tested: bun run check
Not-tested: Full package publish pipeline
---
 .changeset/close-position-path-only.md | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 .changeset/close-position-path-only.md

diff --git a/.changeset/close-position-path-only.md b/.changeset/close-position-path-only.md
new file mode 100644
index 00000000..f89aa468
--- /dev/null
+++ b/.changeset/close-position-path-only.md
@@ -0,0 +1,5 @@
+---
+"@0xmonaco/core": patch
+---
+
+Align close-position requests with the REST contract by keeping `position_id` in the URL path only.