Order Placement Debugging

Systematic approach to fixing strategies that log entry/exit signals but do not place orders, or that hit OpenAlgo smart-order API errors. Use with the order-placement-debugger subagent and debug-mode workflow (hypotheses → instrument → reproduce → analyze → fix → verify).

When to Use

• Strategy logs show SIGNAL: or [ENTRY] /[EXIT] but "Order ID: N/A" or no order ID

• Logs show: Order API Error: Expecting value: line 1 column 1 (char 0) or TradingUtils - ERROR

• HTTP log shows POST .../smartorder "HTTP/1.1 200 OK" but no order in order book

• Adding or fixing placesmartorder / APIClient in a strategy

OpenAlgo Smart Order API (Reference)

Endpoint

Correct Wrong

POST {host}/api/v1/placesmartorder

POST {host}/api/v1/smartorder

Namespace in app: path="/placesmartorder" → full path is /api/v1/placesmartorder .

Request Payload (Required Fields)

Field Type Example Notes

apikey

string OpenAlgo API key Required

strategy

string Strategy name Required

symbol

string e.g. GOLDM05FEB26FUT Required

action

string BUY, SELL Required (not transaction_type )

exchange

string MCX, NSE, NFO Required

pricetype

string MARKET, LIMIT, SL, SL-M Required (not order_type )

product

string MIS, CNC, NRML Required

quantity

string "1" Required; send as string

position_size

string "1" Required; send as string

price

string "0" Optional in API docs but often expected

trigger_price

string "0" Optional

disclosed_quantity

string "0" Optional

Success Response (200)

{ "orderid": "2016727642073505792", "status": "success" }

Common Client-Side Bugs

Wrong URL

Using /api/v1/smartorder → server may return 200 with empty or non-JSON body → response.json() raises "Expecting value: line 1 column 1".

Wrong payload keys

• transaction_type → must be action

• order_type → must be pricetype

Missing fields

Omit price , trigger_price , disclosed_quantity → set to "0" if server expects them.

Wrong types

Sending quantity /position_size as int → send as string (e.g. str(quantity) ).

No handling for non-JSON 200

Calling response.json() on 200 without try/except → on empty/HTML response, catch ValueError , log, and return a safe dict (e.g. {"status": "success", "message": "Order placed (non-JSON response)"} or similar) so strategy does not treat the call as a hard failure.

Code Locations

What Where

Client implementation openalgo/strategies/utils/trading_utils.py → APIClient.placesmartorder()

Strategy usage openalgo/strategies/scripts/*.py (e.g. mcx_global_arbitrage_strategy.py )

Server route openalgo/restx_api/init.py → path="/placesmartorder"

Server handler openalgo/restx_api/place_smart_order.py

Schema/docs openalgo/restx_api/schemas.py (SmartOrderSchema), openalgo/docs/userguide/12-smart-orders/README.md

Hypotheses to Test (With Runtime Evidence)

Use instrumentation (e.g. NDJSON to .cursor/debug.log ) to confirm or reject:

Id Hypothesis What to log Confirmed if

A API client not passed or not initialized In strategy init : has_api_client , host

Log shows has_api_client: false or missing host

B entry() only logs, doesn’t call order API Start of entry() : side , price , has_api_client

No "Attempting order placement" after "entry() called"

C exit() only logs, doesn’t call order API Start of exit() : side , price , has_api_client

No "Attempting exit order placement" after "exit() called"

D Wrong endpoint or payload In placesmartorder() : url , payload keys URL is /smartorder or payload has transaction_type /order_type

E Response not JSON or empty After httpx.post : status_code , content_type , content_length ; then parse content_type not JSON or response.json() raises

Fix Checklist (trading_utils.py)

• URL is f"{self.host}/api/v1/placesmartorder" .

• Payload uses action (not transaction_type ), pricetype (not order_type ).

• Payload includes price , trigger_price , disclosed_quantity (e.g. "0" ).

• quantity and position_size sent as strings.

• On 200, try response.json() ; on ValueError , do not crash—log and return a safe dict.

• On non-200, log response.text and return error dict.

• On exception (e.g. timeout), log and return error dict.

Verification

Minimal test script

Create a script that instantiates APIClient(api_key=..., host=...) and calls placesmartorder(...) with valid args. Run it and check:

• Log: "Order Placed" with a real orderid .

• No "Order API Error" or JSON decode error.

Strategy run

Run the strategy until it generates a signal; check strategy log for [ENTRY] or [EXIT] with a real order ID.

Debug log

If using NDJSON instrumentation, confirm entries for "Response parsed as JSON" and has_orderid: true / status: "success" .

Related

• Subagent: order-placement-debugger — use for full workflow and evidence-based fixes.

• Skills: trading-operations (server/strategy status), log-monitoring (finding entries/errors in logs), trading-strategy-development (strategy structure).

• Docs: openalgo/docs/userguide/12-smart-orders/README.md , openalgo/docs/api/order-management/placesmartorder.md .

Resolved Case (2026-01-29)

Symptom: MCX Global Arbitrage strategy logged signals and "Order placed" but "Order ID: N/A"; log showed Order API Error: Expecting value: line 1 column 1 (char 0) .

Root cause: placesmartorder() in trading_utils.py used wrong endpoint (/api/v1/smartorder ), wrong payload keys (transaction_type , order_type ), missing fields, and called response.json() on 200 without handling non-JSON body.

Fix: Switched to /api/v1/placesmartorder , payload with action , pricetype , price /trigger_price /disclosed_quantity as "0" , string quantity /position_size , and safe handling of non-JSON 200 response.

Verification: Test script called placesmartorder ; response contained orderid and status: "success" . Debug log showed "Response parsed as JSON", has_orderid: true .