Hummerce's REST API exposes store data in JSON format - items, categories, pages, customers, orders, views and other objects - for integrating with ERPs, wholesalers, price comparison sites or your own tools. This is the basic way to connect the store to external systems, alongside ready-made integrations (e.g. Allegro, Microsoft Dynamics NAV, Comarch ERP XL) and the AI assistant (MCP).
As of Hummerce 2.35.74, updated 2026-10-16.
¶ Benefits and use cases
- A single integration standard for many external systems - ERPs, wholesalers, price comparison sites, your own applications - without building an integration from scratch for each one.
- Full access to store data at the staff level - the same objects and permissions as in the admin panel.
- Any scope of permissions - from full admin access to an account restricted to selected objects and operations only.
- Real-time control over order and item data - the external system queries the store directly, without intermediate files or batch import delays.
- Fast integration troubleshooting - store staff and the integrator see in the panel what the external system actually sent and what the store replied, without a support ticket.
REST API exposes:
- Items - including variants and configurable-set slots. An item's categories can be set when saving, also for a variant - see below.
- Categories.
- Pages.
- Customers.
- Views - read, create, update and delete a view; operations on other objects can be run in the context of a chosen view.
- Orders.
- Property types and locations.
- Manufacturers.
- Warehouses and warehouse entries (stock levels).
- Returns - back-office side only (complaint handling in the panel), without the customer filing a return in the store through the API.
- Other store objects (repositories) - e.g. coupons, banners, form submissions, reviews, address book entries.
¶ Authentication and permissions
- The REST API module has to be enabled in the store - it's not active by default.
- Access is granted to a panel admin account: full admin permissions, or permissions restricted to selected API objects and operations.
- Properties meant to be visible in API responses are assigned to dedicated locations - separately for items, categories, pages, customers, views and orders.
- The address the store's API runs on, and the access credentials, are set during implementation.
¶ Categories of items and variants
- When saving an item you can specify a main category and additional categories. From version 2.35.66 this also works for variants (sub-items) - previously the API skipped the categories when a parent item was given.
- A variant's main category is always saved. Whether the variant appears on that category's lists in the store depends on the store setting Variants on the lists - the same as when changing a category in the panel.
- An item without a main category no longer causes an error when its category is changed.
- Since version 2.35.74 the Status -> REST API diagnostics screen shows the last 100 requests received by the API, the last 100 responses sent and the last 100 errors - each error together with the request and response it belongs to - plus hour-by-hour traffic statistics.
- The panel is on after the store update, with no extra configuration. The panel data is kept in memory and counted from the last store start.
- Sensitive data (passwords, tokens, keys) is masked before it reaches the panel or a file.
- Optionally the store saves every request and response in full to files on the server, split by day, hour and type of data (e.g. items, orders, customers, categories). Saving is switched on in the store settings, in the REST API group, and the panel checks on every visit whether saving to files works.
- The AI assistant reads the same data - just ask what came in through the API recently or why a call ended with an error.
- REST standard, data in JSON format.
- Filtering and sorting depend on the object, including by modification date.
- A query parameter lets you set the date format returned in the response, overriding the store's default setting.
REST API and the MCP server (AI assistant) are two independent ways to connect to the store, based on the same admin account permissions:
- REST API - for system integration: ERPs, wholesalers, price comparison sites, your own scripts and applications calling specific methods.
- AI assistant (MCP) - for the support team working with natural-language commands, with a limited set of ready-made tools (not every REST API area has an MCP counterpart and vice versa - e.g. price lists are writable through MCP but not through REST API).
- Warehouses and warehouse entries in the API - since version 2.31.
- Returns in the API (back office only) - since version 2.35.
- Categories when saving variants (sub-items) - since version 2.35.66.
- REST API diagnostics in the panel and in the AI assistant, saving requests to files - since version 2.35.74.
- REST API is developed progressively with further store objects alongside successive platform versions.
- The REST API module enabled in the store.
- An admin account with permissions to the objects and operations exposed by the API.
- Properties assigned to the API locations (separately for items, categories, pages, customers, views, orders), if they need to be visible in the response.
- Requires implementation - the module is not enabled by default. Scope of a typical setup:
- enabling the REST API module,
- creating an account and permissions dedicated to the integration,
- assigning properties to the API locations for the integrated objects,
- testing calls with the target system.
- Minimum estimated time:
- integrating a single area (e.g. only orders or only items) - from 8 h,
- a broader scope (several areas, field mapping on the external system's side) - from 16 h,
- we always add: analysis - +1 h, testing - +2 h, production deployment - +1 h.
- The time for a specific implementation depends on its scope - we quote it individually.
- REST API diagnostics works after updating to version 2.35.74, with no implementation work. Saving requests to files requires a folder prepared on the server - we do it on request.
- What the time depends on:
- the number of integrated data areas,
- the complexity of field mapping on the external system's side,
- a non-standard scope of API account permissions,
- the store version - an older version requires an update first (quoted separately).
- No price list operations - prices are set through an Excel import or through the AI assistant.
- No company account (B2B) management.
- A variant's category saved through the API does not make the variant visible on category lists if the store has the Variants on the lists setting switched off.
- No operations on Allegro offers - that's a separate integration.
- Permissions to objects don't always separate read and write independently - it depends on the object.
- Returns in the API cover only the store's back office, without the customer filing a return in the store through the API.
- The REST API diagnostics panel shows only the last 100 requests, responses and errors since the store started. Older data is available only in files, if saving to files is on.
- REST API has no built-in request-per-minute limit (unlike the MCP server) - too intensive calls can slow the store down. During implementation, we recommend gradually ramping up load and running performance tests before going live.
- We do not verify the task for legal compliance (e.g. licenses of submitted materials, GDPR, store terms of service).
- Separate read and write permissions for all API objects.
- A request-per-minute limit, similar to the MCP server.
- Price list and company account operations in REST API.
Does REST API let you integrate the store with an ERP system?
Yes. REST API exposes items, orders, customers, warehouses and other store objects - a typical way to exchange data with an ERP, alongside ready-made integrations like Comarch ERP XL or Navision.
Can you change price list prices through REST API?
No. Price lists are saved through an Excel import or through the AI assistant - REST API has no price list operations.
Does the API support company accounts (B2B)?
No. Company data is created and changed only by store staff in the panel.
Does REST API have a request-per-minute limit?
No - unlike the MCP server, REST API doesn't limit the number of calls. Too intensive calls can put load on the store, so we recommend performance tests before a production deployment.
How do I check whether an external system sent data to the store?
The Status -> REST API diagnostics panel shows the latest API requests, responses and errors, with sensitive data masked. The AI assistant can read the same. For older data - the request files, if saving is on.
How long does setting up a REST API integration take?
Integrating a single area (e.g. just orders) - from 8 h. A broader scope, with several data areas - from 16 h. The exact time depends on the integration's scope.
Does the AI assistant (MCP) use the same mechanism as REST API?
Not directly. These are two independent ways to connect to the store, based on the same account permissions - REST API for system integration, MCP for the support team working with natural-language commands.
Want to see how REST API could connect your store to another system? Contact the Hummerce team (in Polish).
- Enabling the REST API module and configuring account permissions - in the store configuration.
- API property locations: a separate location for items, categories, pages, customers, views and orders - a property has to be assigned to it to be visible in the API response.
- Status -> REST API diagnostics (since version 2.35.74): latest requests, responses and errors, hourly statistics, state of saving to files (files written and write errors since the start). The setting for saving requests to files - configuration group REST API.
- The address the store's API runs on (the panel address with the API endpoint), and the access credentials for the integration account, are set during implementation.
- Full technical documentation of calls, data models and permission codes - in the Hummerce technical wiki, for the implementation engineer.
¶ REST API and MCP
- The full object and method specification (swagger) is available in the technical wiki.
- The date format parameter in GET requests lets you set the date format returned in the response (e.g. ISO 8601-compliant), overriding the store's default setting.
- Saving an item's and variant's categories: the
categorySymbol (main category) and categoriesSymbol (list of categories) fields; a variant's visibility on lists depends on the store setting item.lists.subitems.
- The MCP server works independently of REST API - see AI assistant - MCP server.
- REST API diagnostics in MCP (since version 2.35.74):
ec2_restapi_diagnostics - latest requests, responses, errors and statistics; ec2_restapi_logs_search - search in the saved request files; ec2_restapi_logs_check - test whether saving to files works.
Parameters exposed in the API are changed in Properties and locations, by assigning them to the API location of the relevant object (item, category, page, customer, view, order).