diff --git a/docs/ENVIRONMENT.md b/docs/ENVIRONMENT.md
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+# Environment Variables
+
+Reference for the environment variables read by the colibrì engine.
+
+**Generated from `upstream/dev @ 6d3ed7e`** by scanning every `getenv()` site in `c/glm.c`. Defaults and behavior are taken from the source; see [MAINTAINING-DOCS.md](MAINTAINING-DOCS.md) to regenerate this after the code changes.
+
+## Which program reads these?
+
+The C engine binary (`c/glm`, built from `c/glm.c`) reads **all** of these. You rarely export them by hand — the `coli` CLI and `openai_server.py` translate most of their flags into these variables before launching `glm` (e.g. `--temp` → `TEMP`, `--ctx` → `CTX`). See [SETTINGS.md](SETTINGS.md) for the flag → variable mapping. Export a variable directly only to reach a knob the CLI doesn't surface, or to override what the CLI would set.
+
+Format: `VAR` — default — effect.
+
+---
+
+## Common — everyday use
+
+| Variable | Default | Effect |
+|---|---|---|
+| `RAM_GB` | `0` (auto ≈ 88% of free RAM) | RAM budget in GB for the resident/streamed expert working set. Higher → more experts stay hot → higher cache hit rate. |
+| `CTX` | `4096` | Maximum context length (tokens) the KV cache is sized for. |
+| `NGEN` | `256` (engine) | Max tokens to generate before stopping (stop tokens can end sooner). `coli --ngen` defaults to `1024`. |
+| `TEMP` | `-1` (auto: `1.0` for chat/text, greedy elsewhere) | Sampling temperature. **`TEMP=0` = greedy/argmax = deterministic.** |
+| `NUCLEUS` | `0.90` | Nucleus (top-p) mass kept when sampling. Slightly tighter than the official 0.95 because the int4 tail is noisy. |
+| `TOPK` | `0` (off) | Top-k filter on the sampling distribution (`0` = no limit). |
+| `TOPP` | `0` (off) | Top-p filter (`0` = use `NUCLEUS`). |
+| `SEED` | unset → seeded from clock + PID | RNG seed for sampling. **Unset = different every run.** Set a fixed value for reproducible sampling. |
+| `KVSAVE` | `1` (on) | Persist the KV cache to `<model>/.coli_kv` so a conversation reopens warm. `KVSAVE=0` disables save+load (lossless round-trip; does not change output). |
+| `KV_SLOTS` | `1` | Number of independent KV conversation slots (1–16), used in serve mode. |
+| `THINK` | `0` (off) | Emit a `<think>` reasoning block. `THINK=1` turns on visible reasoning. |
+| `MTP` | on | Multi-Token Prediction (speculative draft head). `MTP=0` disables it. |
+
+---
+
+## Performance / tuning
+
+| Variable | Default | Effect |
+|---|---|---|
+| `COLI_METAL` | off | Enable the Apple-Silicon Metal GPU backend. Requires a `make METAL=1` build. |
+| `COLI_METAL_GEMM_MIN` | `16` | Minimum matmul rows to dispatch a GEMM to the GPU (below this, stays on CPU). |
+| `COLI_METAL_SPIN` | off | Keep a GPU keep-alive spinner running (reduces dispatch latency; costs power). |
+| `PIPE` | `0` (off) | Overlap expert disk-load with matmul via I/O worker threads. Byte-identical output; reorders I/O. `PIPE=1` opts in. |
+| `PIPE_WORKERS` | `8` | Number of I/O worker threads when `PIPE=1`. Tune to your SSD (fewer avoids over-subscribing cores). |
+| `DIRECT` | `0` (off) | Use `O_DIRECT`/unbuffered reads for expert slabs. Helps sustained NVMe; keeps the zero-copy GPU path. |
+| `COLI_NO_OMP_TUNE` | off | **Kill-switch** for the OpenMP hot-thread tuning (`OMP_WAIT_POLICY=active` spin + proc-bind). Set `=1` when the CPU is mostly waiting on the GPU (Metal) so spin doesn't steal the shared power budget. |
+| `MLOCK` | `-1` (auto: on for macOS) | Wire the streamed expert cache into physical RAM (`mlock`) to dodge the memory compressor. `0` off, `1` force. |
+| `CAP_RAISE` | `1` (on) | Let the engine raise the expert-cache cap above `topk` when RAM allows (bigger batches). `0` fixes the cap. |
+| `PREFETCH` | `0` | Prefetch depth for streamed experts. |
+| `COLI_MMAP` | `0` | `mmap` the weights instead of read()-ing into slabs. |
+| `PIN` | unset | Path to a `.coli_usage` file; pins the hottest experts into a resident "hot store" at startup. |
+| `PIN_GB` | `10.0` | Size budget (GB) for the pinned hot store when `PIN` is set. |
+| `AUTOPIN` | `1` (on) | Auto-pin the hot store from usage history once ≥5000 selections are recorded. |
+| `REPIN` | `0` (off) | Live re-pin the hot store every N emitted tokens (RFC). |
+| `PILOT` | `0` (off) | Router-piloted cross-layer expert prefetch. |
+| `PILOT_REAL` | `0` (off) | Value-preserving real cross-layer prefetch loads (`PILOT_REAL=1` opts in). |
+| `PILOT_K` | `6` if `PILOT_REAL` else `8` | Number of experts the pilot prefetches per step. |
+| `ABSORB` | `-1` (auto: absorbed for S≤4) | MLA attention absorption mode. |
+| `IDOT` | `1` | Integer dot-product kernel. `IDOT=0` uses exact f32 kernels (for A/B numerical checks). |
+| `COLI_POLICY` | `quality` | Resource policy: `quality`, `balanced`, or `experimental-fast`. |
+
+---
+
+## CUDA (NVIDIA)
+
+| Variable | Default | Effect |
+|---|---|---|
+| `COLI_CUDA` | off | Enable the CUDA backend. Requires a CUDA build. |
+| `COLI_GPU` / `COLI_GPUS` | unset | Device selection (`auto`, `none`, or a list like `0,1`). Requires `COLI_CUDA=1`. |
+| `CUDA_DENSE` | `0` | Place dense (non-expert) matmuls on the GPU. |
+| `CUDA_EXPERT_GB` | `0` | VRAM budget (GB) for caching experts on the GPU. |
+| `CUDA_RELEASE_HOST` | auto (`1` if >1 device) | Release host-side copies after upload. |
+| `COLI_CUDA_ATTN` | off | Run S≤4 attention on the GPU. |
+| `COLI_CUDA_PROFILE` | off | Emit CUDA timing. |
+
+---
+
+## Advanced / experimental / debug
+
+These are for testing, benchmarking, or internal use — not part of the everyday surface, and some may change without notice.
+
+| Variable | Default | Effect |
+|---|---|---|
+| `SPEC` | `1` | Speculative decoding on/off. |
+| `DRAFT` | `-1` (auto: 3 with MTP, else 0) | Number of speculative draft tokens per step. |
+| `GRAMMAR` | unset | Path to a GBNF grammar file to constrain generation. |
+| `GRAMMAR_DRAFT` | unset | Max grammar-forced draft span length. |
+| `DSA` | on | Dynamic Sparse Attention indexer. `DSA=0` disables. |
+| `DSA_FORCE` | `0` | Force the DSA path on. |
+| `DSA_TOPK` | model value | Override the DSA index top-k (testing). |
+| `LOOKA` | `0` | Measure router predictability (instrumentation). |
+| `I4_ACC512` / `I4_ACC512_TEST` | off | int4 512-wide accumulator kernel toggle / self-test. |
+| `NOPACK` | off | Disable weight packing. |
+| `DROP` | off | Drop-related debug toggle. |
+| `PIN_FILL` | `0` | Fill the pinned store even without usage data. |
+| `MTP_DEBUG` / `MTP_PRENORM` / `MTP_SWAP` | off | MTP head debugging / ablations. |
+| `STATS` | unset | Write an expert-usage histogram to `STATS=<file>` at end of run. |
+| `SCORE` | unset | Scoring/eval mode over `SCORE=<file>`. |
+| `REF` / `REF_FORCE` | `ref_glm.json` | Reference-output comparison mode. |
+| `REPLAY` | unset | Replay mode. |
+| `TF` | unset | Teacher-forcing mode. |
+| `CHAT_TEMPLATE` | `1` | Apply the GLM chat template (`0` = raw prompt). |
+
+---
+
+## Server / CLI (`openai_server.py`, `coli`)
+
+These are read by the Python programs (not the `glm` engine), so they don't appear in `glm.c`. They cover the OpenAI-compatible server, tool calling, and the debug view.
+
+| Variable | Default | Effect |
+|---|---|---|
+| `COLI_DEBUG` | `0` (off) | Tee the engine transaction to stderr, by level. **`1`** = decoded model output stream only (byte-by-byte, on both the tool-call and plain paths). **`2`** = both sides — the fully-rendered prompt the engine received *and* the output, bracketed and correlated by request id, so stderr reads as the whole conversation. Invaluable for seeing what the model received vs. emitted during an OpenCode session. |
+| `COLI_TOOL_SALVAGE` | `0` (off) | Opt-in de-mangler: reconstruct a malformed int4 tool call by mapping its lone payload onto the tool's primary parameter. Never rewrites well-formed output; recommended for int4 deployments. |
+| `COLI_THINK` | `0` (off) | Make thinking the default when the client sends *neither* `reasoning_effort` nor `enable_thinking`. Any explicit client value still wins. |
+| `COLI_MODEL` | unset | Default model directory (fallback for `--model`). |
+| `COLI_MODEL_ID` | `glm-5.2-colibri` | Model id reported by the API. |
+| `COLI_API_KEY` | unset | Required bearer token for the server. |
+| `COLI_MAX_QUEUE` | `8` | Max queued requests. |
+| `COLI_QUEUE_TIMEOUT` | `300` | Seconds a request may wait in the queue. |
+| `COLI_KV_SLOTS` | `1` | Independent KV conversation slots (→ engine `KV_SLOTS`). |
+| `COLI_POLICY` | `quality` | Resource policy (shared with the engine): `quality` \| `balanced` \| `experimental-fast`. |
+| `COLI_COLOR` | auto (TTY) | `COLI_COLOR=1` forces colored `coli` output when not a TTY. |
+| `COLI_RAW` | `0` | `coli` raw output mode. |
+
+> **Debugging an OpenCode session:** `COLI_DEBUG=1` watches the model's output stream; `COLI_DEBUG=2` shows both sides (prompt + output) as a transcript. Add `COLI_TOOL_SALVAGE=1` on int4 to catch mangled tool calls.
+
+## Set by the CLI (don't usually set by hand)
+
+`coli` / `openai_server.py` set these internally to select a run mode or pass through a flag:
+
+- `SNAP` — model snapshot directory (required by `glm`; set from `--model`).
+- `SERVE`, `SERVE_BATCH` — select serve / batched-serve mode.
+- `PROMPT` — one-shot text mode.
+- `COLI_OMP_TUNED` — internal sentinel guarding the OMP re-exec (see `COLI_NO_OMP_TUNE`); not user-facing.
+
+---
+
+## Worked example — the fast, reproducible Apple-Silicon config
+
+```bash
+# fast (sampling, non-deterministic by design):
+COLI_METAL=1 DIRECT=1 COLI_NO_OMP_TUNE=1 PIPE=1 PIPE_WORKERS=6 MTP=0 \
+  ./coli run --model /path/to/model --ram 113 "your prompt"
+
+# same, but reproducible (greedy):
+TEMP=0 COLI_METAL=1 DIRECT=1 COLI_NO_OMP_TUNE=1 PIPE=1 PIPE_WORKERS=6 MTP=0 \
+  ./coli run --model /path/to/model --ram 113 "your prompt"
+```
diff --git a/docs/MAINTAINING-DOCS.md b/docs/MAINTAINING-DOCS.md
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+# Maintaining these reference docs
+
+`ENVIRONMENT.md` and `SETTINGS.md` are **generated from source**. They carry a "Generated from `main @ <hash>`" line and *will* drift as the code adds knobs. This is the repeatable procedure to refresh them — by hand, or with an AI assistant (e.g. Claude) doing the tedious extraction and table editing.
+
+## Where the truth lives
+
+| Doc | Source of truth | What to scan for |
+|---|---|---|
+| `ENVIRONMENT.md` | `c/glm.c` (and other `c/*.c`) | every `getenv("...")` call — the default and the trailing `/* comment */` |
+| `SETTINGS.md` | `c/coli`, `c/openai_server.py` | every `add_parser(...)` and `add_argument(...)` |
+
+Nothing else defines these. If a knob isn't at one of those call sites, it isn't real.
+
+## Step 1 — extract the current state
+
+Run against the commit you're documenting (use `upstream/dev`, not a local branch):
+
+```bash
+cd <repo>
+git fetch upstream
+HASH=$(git rev-parse --short upstream/dev); echo "documenting $HASH"
+
+# Environment variables (defaults + inline comments):
+git grep -n 'getenv("' upstream/dev -- 'c/*.c'
+
+# CLI settings:
+git grep -nE 'add_parser\(|add_argument\(' upstream/dev -- c/coli c/openai_server.py
+
+# Quick sanity: how many distinct env vars exist now?
+git grep -hoE 'getenv\("[A-Z0-9_]+"\)' upstream/dev -- 'c/*.c' \
+  | sed -E 's/getenv\("(.*)"\)/\1/' | sort -u | wc -l
+```
+
+## Step 2 — diff against what's documented
+
+```bash
+# vars currently in the code:
+git grep -hoE 'getenv\("[A-Z0-9_]+"\)' upstream/dev -- 'c/*.c' \
+  | sed -E 's/getenv\("(.*)"\)/\1/' | sort -u > /tmp/code_vars.txt
+# vars currently in the doc (crude: grab `VAR` cells):
+grep -oE '`[A-Z0-9_]{2,}`' docs/ENVIRONMENT.md | tr -d '`' | sort -u > /tmp/doc_vars.txt
+
+comm -23 /tmp/code_vars.txt /tmp/doc_vars.txt   # in code, NOT documented -> add these
+comm -13 /tmp/code_vars.txt /tmp/doc_vars.txt   # documented, NOT in code -> remove these
+```
+
+## Step 3 — update the tables (AI-assisted)
+
+Paste the Step-1 output to Claude with a prompt like:
+
+> Here are all the `getenv()` sites in `c/glm.c` at commit `<hash>`, and the current `ENVIRONMENT.md`.
+> For each variable: confirm the **default** and **effect** from the code (the ternary default and the `/* comment */`).
+> Update the tables in place — keep the existing grouping (Common / Performance / CUDA / Advanced / Set-by-CLI), add any new variables to the right group, remove any that no longer exist, and fix any default that changed.
+> Do **not** invent behavior: if the comment is thin, describe only what the code literally does. Update the "Generated from" hash to `<hash>`.
+
+Same pattern for `SETTINGS.md` with the `add_argument` output.
+
+Rules that keep it honest:
+- **Defaults come from the ternary**, e.g. `getenv("CTX")?atoi(...):4096` → default `4096`.
+- **Effect comes from the code + inline comment only** — never from memory or assumption.
+- A variable with no flag stays env-only; note it as such.
+- Keep experimental/debug knobs in the **Advanced** section so nobody mistakes them for supported surface.
+
+## Step 4 — verify
+
+- Re-run the Step-2 diff — both `comm` outputs should be empty.
+- Spot-check 3–5 defaults by eye against `git grep`.
+- Bump the "Generated from `main @ <hash>`" line in both docs.
+
+## Cadence
+
+Refresh when: a release is cut, or `git grep -c 'getenv(' c/glm.c` changes, or someone reports a knob that isn't documented. A one-line CI check (compare the code-var count to a committed number) can flag drift automatically.
diff --git a/docs/SETTINGS.md b/docs/SETTINGS.md
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+# CLI & Settings Reference
+
+Command-line settings for the two user-facing programs: the **`coli`** CLI and the **`openai_server.py`** server. The underlying `glm` engine is driven by environment variables — see [ENVIRONMENT.md](ENVIRONMENT.md).
+
+**Generated from `upstream/dev @ 6d3ed7e`** (argparse definitions in `c/coli` and `c/openai_server.py`). See [MAINTAINING-DOCS.md](MAINTAINING-DOCS.md) to regenerate.
+
+---
+
+## `coli` — the CLI
+
+```
+coli <subcommand> [flags]
+```
+
+Flags may also be given **after** the subcommand. Most flags map onto an engine environment variable before `glm` is launched (see the mapping table at the bottom).
+
+### Subcommands
+
+| Subcommand | Purpose |
+|---|---|
+| `build` | Build/prepare the engine. |
+| `info` | Print model / build info. |
+| `plan` | Show the computed RAM/VRAM placement plan (`--json` for machine-readable). |
+| `doctor` | Environment/health check (`--json` for a versioned report). |
+| `run "<prompt>"` | One-shot generation for the given prompt (positional, may be multi-word). |
+| `chat` | Interactive REPL chat. |
+| `serve` | Start the OpenAI-compatible HTTP server. |
+| `bench [tasks]` | Run benchmark tasks (`--limit`, `--data`). |
+| `convert` | Convert an FP8 repo to a colibrì int4 snapshot. |
+
+### Common flags (all subcommands)
+
+| Flag | Default | Maps to | Meaning |
+|---|---|---|---|
+| `--model` | `$COLI_MODEL` or built-in path | `SNAP` | Model snapshot directory. |
+| `--ram` | `0` (auto ≈ 88% free) | `RAM_GB` | RAM budget in GB for the expert working set. |
+| `--ctx` | `0` (auto) | `CTX` | Context length. |
+| `--cap` | `8` | `<cap>` argv | Expert-cache cap (starting point; see `CAP_RAISE`). |
+| `--ngen` | `1024` | `NGEN` | Max tokens to generate. |
+| `--temp` | none (`0`=greedy; engine default 1.0) | `TEMP` | Sampling temperature. |
+| `--topp` | `0` | `TOPP` | Top-p filter. |
+| `--topk` | `0` | `TOPK` | Top-k filter. |
+| `--repin` | `0` | `REPIN` | Re-pin experts every N tokens. |
+| `--policy` | `quality` | `COLI_POLICY` | `quality` \| `balanced` \| `experimental-fast`. |
+| `--gpu` | `None` | `COLI_GPU(S)` | `auto`, `none`, or a device list like `0,1`. |
+| `--vram` | `0` (auto) | CUDA plan | Total VRAM budget in GB. |
+| `--auto-tier` | off | resource plan | Automatically apply the RAM/VRAM placement plan. |
+
+### Subcommand-specific flags
+
+**`serve`**
+
+| Flag | Default | Meaning |
+|---|---|---|
+| `--host` | `127.0.0.1` | Bind address. |
+| `--port` | `8000` | Port. |
+| `--model-id` | `$COLI_MODEL_ID` or `glm-5.2-colibri` | Model id reported by the API. |
+| `--api-key` | `$COLI_API_KEY` | Require this bearer token. |
+| `--cors-origin` | none (repeatable) | Allowed CORS origin(s). |
+| `--max-queue` | `$COLI_MAX_QUEUE` or `8` | Max queued requests. |
+| `--queue-timeout` | `$COLI_QUEUE_TIMEOUT` or `300` | Seconds a request may wait. |
+| `--kv-slots` | `$COLI_KV_SLOTS` or `1` | Independent KV conversation slots (→ `KV_SLOTS`). |
+
+**`convert`**
+
+| Flag | Default | Meaning |
+|---|---|---|
+| `--repo` | `zai-org/GLM-5.2-FP8` | Source FP8 repo. |
+| `--ebits` | `4` | Streamed-expert bit width. |
+| `--io-bits` | `8` | Resident (attention/dense/embed) bit width. |
+| `--xbits` | `0` | Extra/override bit width. |
+| `--no-mtp` | off | Skip the MTP speculative-draft head. |
+
+**`bench`**: `[tasks...]` (positional), `--limit 40`, `--data <bench dir>`.
+**`plan` / `doctor`**: `--json`.
+
+---
+
+## `openai_server.py` — the HTTP server
+
+Run directly (or via `coli serve`). OpenAI-compatible `/v1/chat/completions`.
+
+| Flag | Default | Meaning |
+|---|---|---|
+| `--model` | `$COLI_MODEL` (required if unset) | Model snapshot directory. |
+| `--engine` | `./glm` | Path to the engine binary. |
+| `--host` | `127.0.0.1` | Bind address. |
+| `--port` | `8000` | Port. |
+| `--model-id` | `$COLI_MODEL_ID` or `glm-5.2-colibri` | Model id in API responses. |
+| `--api-key` | `$COLI_API_KEY` | Required bearer token. |
+| `--cors-origin` | none (repeatable) | Allowed CORS origin(s). |
+| `--cap` | `8` | Expert-cache cap. |
+| `--max-tokens` | `1024` | Default max completion tokens. |
+| `--max-queue` | `$COLI_MAX_QUEUE` or `8` | Max queued requests. |
+| `--queue-timeout` | `$COLI_QUEUE_TIMEOUT` or `300` | Request queue timeout (s). |
+| `--kv-slots` | `$COLI_KV_SLOTS` or `1` | KV conversation slots. |
+
+Tool calling (`tools` in the request) is supported; the opt-in `COLI_TOOL_SALVAGE=1` env var recovers malformed int4 tool calls. Server-relevant env vars: `COLI_METAL`, `PIPE`, `DIRECT`, `COLI_NO_OMP_TUNE`, `RAM_GB`, `CTX`, `KVSAVE` (all from [ENVIRONMENT.md](ENVIRONMENT.md)) apply because the server launches the same `glm` engine.
+
+---
+
+## Flags vs environment variables
+
+A flag and its mapped environment variable are two routes to the same engine knob. Precedence and coverage:
+
+- For knobs with a flag (`--temp`, `--ctx`, `--ram`, `--topk`, `--topp`, `--repin`, `--cap`, `--ngen`, `--policy`), prefer the flag — it's the supported surface.
+- For knobs with **no** flag (`COLI_METAL`, `PIPE`, `DIRECT`, `COLI_NO_OMP_TUNE`, `MLOCK`, `CAP_RAISE`, `KVSAVE`, `SEED`, `NUCLEUS`, …), export the environment variable.
+- The CLI copies your whole environment through to `glm`, so any variable you export is honored unless a flag explicitly overrides it.