Outcome: point a fetch-capable or tool-enabled assistant at this language.
Prerequisite: none for the first section. The MCP server needs the toolchain installed as described in First Program.
Start with one fetch
For an assistant that can retrieve a URL but has no tools configured, the widest common surface is a single self-contained file.
https://topaz.ooo/agents.mdIt carries the shape of a file, the forms, the host/profile boundary, and the section that matters most for a model that already knows other languages: an explicit list of non-forms. It warns against Vec<T>, async, try, class syntax, and treating null as universal absence, while preserving the supported T | null data-boundary form. Naming those distinctions prevents confident guesses from becoming invalid source.
Several machine surfaces sit beside it. https://topaz.ooo/llms.txt is the
compact index, while https://topaz.ooo/llms-full.txt contains the complete
English manual as plain Markdown. Every English page is also available at
https://topaz.ooo/docs/<slug>.md, with its title, source route, and covered
specification sections preserved in frontmatter.
https://topaz.ooo/version.json states which version answers.
If you are configuring an assistant for someone else, giving it that one URL is the whole setup.
The problem the tools solve
Fetching gets an assistant to correct forms. It does not tell it whether the program it just wrote actually compiles.
An assistant writing an unfamiliar language does one of two things. It reads documentation and guesses, or it writes, gets told exactly what is wrong, and fixes it. The second loop produces working code even when documentation is thin. The first produces confident text that does not compile. A reference alone leaves an assistant in the first loop. A checker moves it to the second.
Four published tools
| Tool | What it answers |
|---|---|
topaz_spec | What is the exact form for this part of the language? |
topaz_examples | Show me verified code for this concept. |
topaz_check | Is what I just wrote correct, and if not, exactly where? |
topaz_run | What does this program return inside the no-capability run boundary? |
topaz_check returns the compiler's own diagnostics, codes, and source
positions without rewriting them. topaz_run first performs that check and
then starts a fresh worker. Both tools report the exact installed toolchain
and compiler selection that answered, so an assistant can correct its output
from evidence rather than a paraphrase.
Execution boundary
Each topaz_run call starts the hidden worker in the same installed Topaz
executable with a fresh no-capability host. It has no filesystem, network,
discovery, callback, component, or fallback route. The server admits two active
runs, queues none, applies a five-second wall limit and a one MiB response
limit, and kills and reaps cancelled or limited workers. Submitted source is
sent through stdin and is neither logged nor retained.
This authoring boundary is available on every supported native Topaz target.
It is not ordinary unrestricted topaz run, but it is also not an operating
system sandbox or a hard CPU or RSS bound. Do not submit adversarial code.
Machine-readable descriptor
Clients and crawlers can read the server description directly.
https://topaz.ooo/mcp.jsonIt lists the four tools, their inputs, the built-in command, resource boundary, and installed self-check values in structured form.
Current status
Topaz 5.18.1 includes the MCP server and worker in the native topaz
executable. Installing Topaz installs the MCP server. There is no separate
archive, checksum, server path, worker path, or admission path.
Install and connect
Install Topaz, then configure this local stdio command.
{
"command": "topaz",
"args": ["mcp", "serve"]
}
After connecting, the client must discover exactly topaz_spec,
topaz_examples, topaz_check, and topaz_run. The verification block in
mcp.json provides a known reference section,
example concept, clean source check, and pure run with value 42. These let a
client confirm the installed server instead of trusting configuration alone.
Ready to continue when
You can use exact reference material, repair a program from compiler diagnostics, and run pure source through the installed no-capability worker.
For what a program can and cannot reach, see Interop Boundaries. For the forms an assistant will be looking up, see Syntax at a Glance.