For programs and assistants
Use this site with an AI assistant
Every reference page here is published a second time in a form a program can read without guessing at a web page. This page lists those forms, shows how to point an assistant at them, and says what to be careful of.
Risk warning: CFDs and spread bets are complex instruments and come with a high risk of losing money rapidly due to leverage. You can lose money on these products, and each provider publishes its own loss figure under FCA rules. You should consider whether you understand how they work and whether you can afford to take the high risk of losing your money. Automated and API trading can amplify losses through bugs, connectivity failures and runaway orders.
An assistant can misread a page, mix up two brokers or state an unverified fact as settled. Check the source link beside a fact before you rely on it. Nothing here is advice, and never paste an API key, a password or a token into a chat.
What exists for machines
- llms.txt
- The index: what the site is, how to read its facts, and a linked list of its pages and files. It follows the layout set out at llmstxt.org. Start an assistant here.
- llms-full.txt
- The core reference in one markdown file of about 423 KB: every broker and platform record with its claims and limits, every endpoint by method and path, every function and message by name with each streaming interface described, and every error code with its HTTP status and the address of its page.
- Markdown pages
- 2,499 pages have a markdown version at the page address plus .md: 21 broker pages, 8 platform pages, 359 endpoint pages, 215 function and message pages, 1,776 error code pages (one for each error code this site counts), 7 longer pages about one error each (not counted as error codes), 29 rate limit pages, 10 quickstarts, 37 guides and 37 answer pages. For example /brokers/capital-com.md. Each file is written from the same records as its page and carries every status, source and checked date, the full risk warning, the licence and how to cite. A guide written as a page of its own, such as the getting started guide, is written from the same data as its page.
- JSON and CSV downloads
- The registers as files at stable addresses, and 29 files that each hold everything recorded for one broker or platform, such as /data/brokers/capital-com.json. The licence of each is stated on the downloads page and in the file.
- OpenAPI files
- 12 OpenAPI 3.1 files generated from the endpoint records, such as /specs/capital-com.json. Each is this site's own description, not the broker's specification, and every operation carries its source and checked date.
- Practice API
- Fixed JSON files of invented data at https://openbrokerapi.com/mock/v1 that answer a real GET request with no account and no key. It is not any broker's API. Use it to let an assistant write and run a first request safely. It is described as an OpenAPI 3.1 file at /mock/v1/openapi.json, which an assistant or an API tool can load.
- Change feed
- Dated changes to broker and platform APIs as a feed, and grouped by week.
These files are served as plain files. Any origin may fetch them, and they are sent with the content type that matches each one. A markdown version is marked so that search engines index the page and not its copy.
How to point an assistant at it
Give it the index
Paste the address of llms.txt into the conversation, or attach llms-full.txt if your assistant cannot open links. Ask it to read that before it answers.
Give it the page you care about, as markdown
Add .md to the address of a broker, platform, endpoint, function, message, error, rate limit, quickstart, guide or answer page. The markdown file holds the same facts with no navigation around them, so less is lost on the way in.
Ask for the source with every fact
Each fact in these files carries a status, a source link and a checked date. Tell the assistant to repeat all three, and to say unverified where the file says unverified.
For a program, use the data files
A script should read JSON or CSV from the downloads, or an OpenAPI file, and not a web page. The addresses are stable.
An instruction you can adapt:
Read https://openbrokerapi.com/llms.txt first. It lists what the site holds. For Capital.com, read https://openbrokerapi.com/brokers/capital-com.md Answer only from those pages. For each fact give its status, its source link and its checked date. If a fact is marked unverified, say that it is unverified. If the site holds no record, say so.
This site's own MCP server
MCP, the Model Context Protocol, is a standard way for an assistant to call outside tools. A server for this site's reference data has been built and tested in the site's repository. It is not published yet: it is not on npm, not in the MCP registry and not hosted anywhere, so there is no install command to give you today. Until it is, the files above are the way in.
- What it does
- Reads this site's published downloads and nothing else. It never contacts a broker.
- What it cannot do
- It takes no credential and has no trading tools. It cannot place, change or cancel an order and it holds no account.
- Its tools
- 12 tools, all read only: list_brokers, get_broker, list_endpoints, get_endpoint, get_rate_limits, lookup_error, list_calls, get_call, find_api, compare_capability, what_changed, list_mcp_servers. Every result carries the status, source and checked date of what it returns.
That is this site's server. For servers that connect an assistant to a broker or a platform, see which brokers have an MCP server: each is marked official or community, with whether it can place orders.
Cautions
- An assistant can misread. It may swap two brokers, drop the scope of a limit or turn an unverified line into a plain statement. Open the source link and read it yourself.
- A checked date is the day a source was last opened. The broker may have changed its API since. Where this site and a broker's own documentation differ, the documentation wins.
- Not recorded means this site holds no record. It does not mean the broker lacks the thing, and an assistant should not say that it does.
- Nothing here is advice. The site does not recommend a broker or a trade, and an answer built from it should not either.
- Never paste an API key, a password or a token into a chat. No file or page on this site needs one.
- Code an assistant writes from these pages has not been run against your account. Try it on a demo account first, and on the practice API before that.