yurivict connected crush per the walkthrough and got 'thought for 1h8m and did nothing' — which is not a hang: agent CLIs send a 10-20k-token system preamble, and prefill on the CPU-streaming path runs at a few tok/s (attention-bound, #153). An hour of silent prefill looks exactly like a dead server. The note now spells out the arithmetic, the curl smoke-test that separates slow-but-working from broken, and honest guidance on what agent workloads are (not) viable. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
7.9 KiB
OpenAI-compatible API, KV contexts & web UI
coli serve
coli serve keeps one model process loaded and exposes a text-only
OpenAI-compatible HTTP API. The gateway uses only the Python standard library;
inference still runs in the same dependency-free C engine.
cd c
COLI_MODEL=/nvme/glm52_i4 COLI_API_KEY=local-secret ./coli serve \
--host 127.0.0.1 --port 8000 --model-id glm-5.2-colibri
curl http://127.0.0.1:8000/v1/chat/completions \
-H 'Authorization: Bearer local-secret' \
-H 'Content-Type: application/json' \
-d '{
"model": "glm-5.2-colibri",
"messages": [{"role": "user", "content": "Hello"}],
"stream": true
}'
Implemented endpoints are GET /v1/models, GET /v1/models/{model},
POST /v1/chat/completions, and legacy POST /v1/completions. Chat and
completion requests support JSON responses, SSE streaming, usage counts,
max_tokens/max_completion_tokens, temperature, and top_p. The extension
enable_thinking: true enables GLM-5.2's reasoning block; the standard
reasoning_effort field also enables it unless set to none.
The server is deliberately text-only and serves one generation at a time: the
744B model stays in one persistent process, so concurrent HTTP requests queue
instead of loading duplicate model copies. Tools, image/audio input, custom
stop sequences, log probabilities, and token penalties return an explicit error
rather than being silently ignored. The default bind address is localhost; set
COLI_API_KEY before exposing the server beyond the machine.
Browser access from the Vite development server and Tauri local origins is
enabled by default. Repeat --cors-origin https://your-ui.example to allow
another exact origin, or use --cors-origin '*' only on a trusted local
network.
The engine owns its KV contexts, so HTTP generation uses a bounded FIFO
admission queue instead of pretending to run unsafe parallel sequences.
Configure it with --max-queue N (default 8) and --queue-timeout SECONDS
(default 300), or the COLI_MAX_QUEUE / COLI_QUEUE_TIMEOUT environment
variables. Saturated and timed-out requests receive OpenAI-shaped HTTP 429
errors before streaming headers are sent. GET /health exposes
active/queued/completed/rejected counters, and successful generation responses
include x-colibri-queue-wait-ms.
Connect a coding CLI or editor
The API is OpenAI-compatible, so most coding CLIs and editor extensions work by pointing them at Colibri as an OpenAI-compatible provider. Three settings:
- Base URL —
http://localhost:8000/v1 - Model —
glm-5.2-colibri(or whatever you pass to--model-id) - API key — any non-empty string, e.g.
local
Colibri needs no API key by default, but many clients refuse to start without
one — give them any dummy value. The key is only enforced if you set COLI_API_KEY.
Smoke-test the endpoint first (no key needed unless you set one):
curl http://127.0.0.1:8000/v1/chat/completions \
-H 'Content-Type: application/json' \
-d '{"model":"glm-5.2-colibri","messages":[{"role":"user","content":"hi"}]}'
aider
export OPENAI_API_BASE=http://localhost:8000/v1
export OPENAI_API_KEY=local
aider --model openai/glm-5.2-colibri # the openai/ prefix routes to OPENAI_API_BASE
crush — add a provider to crush.json (~/.config/crush/crush.json, or
%USERPROFILE%\AppData\Local\crush\crush.json on Windows):
{
"$schema": "https://charm.land/crush.json",
"providers": {
"colibri": {
"name": "Colibri",
"type": "openai-compat",
"base_url": "http://localhost:8000/v1/",
"api_key": "local",
"models": [
{ "name": "GLM-5.2 (Colibri)", "id": "glm-5.2-colibri",
"context_window": 131072, "default_max_tokens": 1024 }
]
}
}
}
The "api_key": "local" dummy is what satisfies clients that demand a key.
context_window is only the client's budget display — set it to whatever your
KV configuration actually allows.
Continue, Cline / Roo, llm, the OpenAI SDKs, … — set the provider's base
URL to http://localhost:8000/v1, the model to glm-5.2-colibri, and any dummy
key (OPENAI_API_KEY / OPENAI_BASE_URL for env-based tools).
Set your expectations before connecting an agentic CLI. Two costs dominate, and the first one is invisible until you know it's there:
- Prefill. Coding agents (crush, aider in repo-map mode, Cline, …) send a large system prompt plus tool definitions — often 10–20k tokens — before your first word. Prefill on the CPU-streaming path runs at a few tokens per second (it is attention-bound, see #153), so a 15k-token agent preamble is an hour of silent "thinking" before the first output token. The client looks hung; it isn't. Smoke-test with the tiny
curlabove first — if that answers in about a minute, the pipeline works and what you're paying for is prompt size.- Decode. Roughly 1 tok/s for a large model, so multi-turn agent loops (which re-pay the growing context every turn) compound the cost.
Practical guidance: single surgical asks with a short context work; iterative agent sessions against a disk-streaming 744B model do not resemble a hosted API and mostly won't be worth the wait. If your client lets you trim or disable its system preamble and tool catalog, do it.
Isolated KV contexts
coli serve --kv-slots N allocates up to 16 independent sequence contexts.
Requests select one with the optional integer cache_slot field; ordinary
OpenAI clients omit it and keep the original slot 0 behavior.
{
"model": "glm-5.2-colibri",
"messages": [{"role": "user", "content": "Continue this conversation"}],
"cache_slot": 1
}
Each slot owns its token history, compressed MLA/DSA KV memory, MTP window, and
crash-safe persistence file (.coli_kv, .coli_kv.1, ...). The engine matches
each request's tokenized prompt against the slot's history and reuses the common
KV prefix, so stateless HTTP turns keep their cache across requests and even
across engine restarts. Use COLI_KV_SLOTS=N as the environment equivalent.
Start small: at the default 4096-token context, every slot costs hundreds of MB.
Web dashboard
One command serves the OpenAI-compatible API and the web console on the same port, then opens your browser when the engine is ready:
cd web && npm install && npm run build # once
./coli web --model <model-dir>
What you get:
- Chat with live metrics: a flashing token counter while generating, then tok/s, time-to-first-token, prompt→completion counts and queue wait;
- Runtime panel: your hardware (CPU, GPUs + VRAM, RAM, cores), the scheduler, and the live expert-tier bar — how many of the 19,456 experts sit in VRAM / RAM / disk right now;
- Brain: the whole model as a 76×256 cortex, one cell per expert. Colour = tier, brightness = routing heat, and the experts routed in each turn flash white and decay — you watch the model think. Hover any cell for its tier, heat and measured topic affinity;
- Atlas: the measured expert atlas as a 3-D galaxy (publish
experts.jsonfromtools/expert_atlas/analyze.py --web).
The dashboard talks to the engine over a small line protocol and plain JSON
endpoints — nothing heavier than the engine itself. web/ is a pure OpenAI-API
client (React + TypeScript) and also works against any other compatible
endpoint; the terminal coli chat remains the first-class interface.
The layout is responsive down to phone widths, and the sidebar carries the full telemetry stack — hardware, scheduler, tier bar, per-turn time breakdown, tok/s trend and per-GPU expert counts:

