BT AI development guide

BT AI development guide

Function

The BT website provides public knowledge endpoints for coding assistants, IDEs, and documentation tools. They cover language semantics, syntax, the standard library, Web and desktop development, networking, devices, extensions, and FFI. Clients can retrieve only the material needed for a task.

When providing a separate URL to the AI, use the following:

The guide instructs clients to search first, then read the relevant function contract, document, stable knowledge block, or module. These endpoints return public documentation only; they do not accept user questions, project source, model configuration, accounts, API keys, or private data.

Language and canonical URLs

The AI guide, reference modules, function contracts, search results, and current offline bundle use English as their authoritative language. Chinese category keywords remain available as search aliases. Assistants should respond in the user's requested language and follow the target project's code conventions.

Human documentation remains available in English and Simplified Chinese. All localized website URLs put the language first: /en/docs/{path}, /zh-hans/docs/{path}, /en/md/docs/{path}, and /zh-hans/md/docs/{path}. AI search links always select English explicitly, independently of browser language or cookies. /ai and /llms.txt remain global English machine entry points.

Legacy /md/docs/en/{path} redirects permanently to /en/md/docs/{path}. /md/docs/zh-hans/{path} and the historically Chinese /md/docs/{path} redirect to /zh-hans/md/docs/{path}. The zh-cn alias and language-tag casing normalize to lowercase zh-hans or en. Missing document paths default to index; missing documents and unsafe paths return 404.

Syntax

Recommended reading order:

1. Read only /ai for the first time;

2. Use /ai/search to query the API name, module name or runtime name;

3. Use a symbol contract directly. For a doc result, read markdown_url; for a block result, read content_url.

4. Read the entire module only when the system design or semantics are uncertain;

5. The complete index and offline package are only for client caching, offline development or knowledge tool integration.

Parameters

Path Parameters

Query Parameters

Conditional request header

Return Value

AI guide

GET /ai returns a condensed plain text with Markdown structure as text/plain; charset=utf-8 to avoid rejection of response by AI crawling components that only accept common web page text types. The main text includes:

• the most token-saving forced reading strategy;
• search, precise documentation, knowledge blocks, modules and offline package addresses;
• module routing, dependency and token estimation;
• shorthand for running, building and accepting BT and bt-app.

It is not a full document, and AI should not guess specific function signatures based only on the entry summary.

Knowledge Manifest

GET /ai/manifest Returns UTF-8 JSON:

modules[] Field:

Search for

GET /ai/search by keyword Return small UTF-8 JSON:

results[] Common fields and branch fields:

Full Search Index

GET /ai/index Returns a JSON index of all accurate documents and stable knowledge chunks. It is suitable for IDE or local tools to build caches, but is not suitable for direct use as a model context for ordinary coding tasks.

Single knowledge block and the entire module

GET /ai/block/{module_id}/{block_name} returns only a stable Markdown knowledge block; GET /ai/knowledge/{module_id} returns the entire module. Both transfer Markdown body as text/plain; charset=utf-8 and provide SHA-256 and conditional caching response headers.

Knowledge chunks are usually much smaller than the entire module. For example, when you only need the String method summary, you should read the corresponding knowledge block; when you only need the precise signature of string.replace, you should directly use the symbol function contract in the search results.

Complete offline package

GET /ai/bundle/{knowledge_version} Returns bt-ai-bundle-json-v1 JSON:

Response headers

Code Examples

The following BT script searches for string.replace, reading the minimal function contract directly:

The following BT script verifies a single knowledge block by manifest:

Notes

• Normal coding tasks do not read the full search index, the full module set, or the offline package; search first and read by minimal results.
• /llms.txt is an automatically discovered alias agreed by AI tools, and the text format is still Markdown; only https://btlang.org/ai is used when developers actively provide links.
• AI portals, precise documentation, knowledge blocks and modules intentionally use the more compatible text/plain and do not change back to text/markdown which may be rejected by some web page reading components.
• When the API name is known, search for category api_name or the complete symbol first, such as string replace, mysql begin, window.bt.call.
• The same development task should always use one knowledge_version, and do not mix two versions in the middle of the task.
• Modules, knowledge blocks, indexes or offline packages should be SHA-256 verified against the original UTF-8 bytes after downloading before being written to the official cache.
• The 304 response has no body, the client should continue to use the local verified content.
• When the official website is inaccessible, the tool can fall back to its own built-in and verified complete package; ordinary projects must not assume the existence of fixed local directories such as E:\bt-lang.
• The project's own AGENTS.md, README, runtime file locations and test commands take precedence over this site's general recommendations.
• Unknown paths, modules or knowledge blocks return 404, missing search terms return 400, non-GET requests return 405.