ProjectX vs TopstepX: Platform, API, and Permission Explained

The names appear together because TopstepX API access uses ProjectX infrastructure and documentation. They should not be treated as interchangeable legal or account concepts. ProjectX documents the technical API: authentication, account search, contracts, orders, positions, history, and real-time data hubs. Topstep controls who may link a TopstepX profile, which Topstep accounts are eligible, and what trading behavior is allowed at each account stage.

This distinction matters whenever a connector asks for a platform type. Selecting ProjectX usually describes the protocol family the software will speak. Selecting or linking TopstepX identifies the branded destination and account context. Neither label by itself grants permission to automate. Technical connection is not permission; private server order relay and Live Funded API limits must be verified in the current official rules before every deployment.

A developer troubleshooting an HTTP request should look to the ProjectX Gateway reference. For example, the documented order placement route is a POST to the TopstepX API order endpoint with accountId, contractId, type, side, and size. Optional price and bracket objects depend on order type. Rate-limit documentation currently separates historical bar retrieval from other authenticated endpoints and describes HTTP 429 behavior.

A trader deciding whether the request is allowed must read Topstep's current materials. Topstep's API-access instructions describe creating a ProjectX Dashboard account, purchasing API access, linking that subscription to the TopstepX profile, and generating a key inside TopstepX. The same help article imposes device and remote-server restrictions. The Live Funded parameters separately describe limits for the LFA stage. Code should not infer policy from a successful login.

ProjectX documents integer order-type and side values. At the reviewed date, type 1 is Limit, 2 is Market, 4 is Stop, 5 is TrailingStop, 6 is JoinBid, and 7 is JoinAsk; side 0 is Bid and side 1 is Ask. An integration should use the current reference rather than freezing those values in an unreviewed spreadsheet. Limit, stop, and trail prices are optional only when they do not apply to the selected order type.

The strategy-facing payload should not expose those protocol details unless necessary. A normalization layer can accept buy, sell, market, limit, and a root symbol, then resolve an eligible account and exact contract. It should preserve the source event ID in a unique custom tag when appropriate and enforce uniqueness rules. The response's success field and orderId are broker acknowledgements, not evidence that the order filled.

The separate steps explain a frequent User lacks subscription error. Buying ProjectX API access does not automatically associate it with a TopstepX profile. The current Topstep flow starts in the ProjectX Dashboard, then requires a ProjectX Linking action from the TopstepX API settings, confirmation that the account appears in the ProjectX Dashboard, and finally key generation in TopstepX.

Treat the generated key like a password. Topstep warns that it grants trading access to every eligible account under the profile. Store it in a protected local secret store, never in Pine Script, a webhook body, browser source, public repository, or support screenshot. If a key is exposed, rotate it and update every authorized client. A connector should list accounts after authentication and require an explicit account allowlist rather than trading the first result.

Topstep's current API-access article permits custom bots subject to platform rules and its HFT prohibition, but it also says all trading activity must originate from the trader's personal device. The article prohibits VPS, VPN, and remote-server use for order flow, including placing, changing, cancelling, triggering, routing, or relaying orders. A private server may perform listed supporting work such as research, historical storage, logging, analytics, read-only dashboards, and receiving copies of the trader's own state.

The Live Funded Account page creates another boundary: automated strategies may be permitted generally, but automated trading through the ProjectX API is stated to be prohibited in the LFA. Do not generalize permission from a Practice, Trading Combine, or Express Funded test to Live Funded. Technical connection is not permission; private server order relay and Live Funded API limits must be verified in current official rules.

A robust platform record should contain provider type, credential reference, discovered account ID, allowed contract roots, risk caps, and account stage. It should not use an email address as an order account ID or assume every account returned by the profile is eligible. Contract search and account discovery happen before the first signal is armed, and the resulting identifiers should be visible to the operator.

Keep policy controls outside the protocol adapter. The adapter answers whether it can authenticate, subscribe, and submit. A deployment gate answers whether it may do so for this firm, account stage, device, and strategy. This separation avoids a dangerous implementation pattern where successful technical discovery automatically enables trading. It also makes a later policy change enforceable without rewriting order code.

Start with a dated policy capture: URLs, review date, applicable stage, and the exact restriction governing automation and hosting. Next, authenticate from the permitted device and retrieve accounts. Select one intended account, resolve one current micro contract, and perform a read-only state check. If Topstep currently offers no separate sandbox, follow its direction to use the appropriate Practice account rather than risking an Evaluation account.

Only then exercise the minimum order lifecycle allowed by the account: submit, observe acknowledgement, observe fill or cancellation, and reconcile the resulting position. Test expired authentication, an unknown contract, a duplicate custom tag, HTTP 429 handling, and a lost real-time connection. Stop if the tool cannot prove which account it will trade or if a stage change invalidates the approved path.