Pi
Pi reads its providers from a single global JSON file rather than environment variables, so
opencodex does not launch it. Instead, ocx export serializes the opencodex provider block —
base URL, model list, and the env reference Pi interpolates — and you merge it into your own
config.
Quickstart
Section titled “Quickstart”Start the proxy, then print the config:
ocx startocx export --client piThe output leads with the JSON, then prints the destination path, the merge warning, the env export line, and how many models carry authoritative context limits.
{ "providers": { "opencodex": { "baseUrl": "http://127.0.0.1:10100/v1", "api": "openai-completions", "apiKey": "$OPENCODEX_API_KEY", "compat": { "sendSessionAffinityHeaders": true }, "models": [ { "id": "anthropic/claude-opus-5", "name": "Claude Opus 5 (anthropic)", "input": ["text"], "contextWindow": 200000, "maxTokens": 32000 } ] } }}Generated Pi providers enable compat.sendSessionAffinityHeaders. Keep this flag when merging or manually editing the provider: Pi supplies a stable session identity and OpenCodex derives canonical OpenCode Go affinity from it. Pi may omit the identity when cacheRetention is none.
Model ids are the proxy’s canonical selectors, so routed models appear as provider/model
(anthropic/claude-opus-5) and native OpenAI slugs stay unprefixed (gpt-5.6-sol). The name
suffix — (anthropic), (native), (routed) — is what makes two same-named models from
different upstreams distinguishable in Pi’s picker.
Where it goes
Section titled “Where it goes”Pi’s global model config is:
~/.pi/agent/models.jsonThe exported block is a static snapshot, not a live view. Re-run ocx export after adding a
provider or changing model visibility, and merge the new block over the old one.
The admission key
Section titled “The admission key”Two different keys are easy to confuse here, and only the first one appears in this file:
| Key | What it is | Where it lives |
|---|---|---|
| Proxy admission key | opencodex’s own credential, generated on the dashboard’s API tab | referenced by apiKey as $OPENCODEX_API_KEY; the value stays in your environment |
| Provider key | your Anthropic / OpenAI / OpenRouter key | opencodex’s own config, per Providers |
The exported config carries only the reference, never a secret. Pi interpolates a bare $NAME, so
the variable is:
export OPENCODEX_API_KEY=<your key>That name is Pi’s alone. opencode uses a different variable
(OPENCODEX_OPENCODE_API_KEY, in {env:…} form) — see the opencode guide.
A loopback proxy needs no key at all. opencodex binds 127.0.0.1 by default and authenticates
nothing there, so the $OPENCODEX_API_KEY reference is inert and you can leave the variable unset.
It matters only when hostname is set beyond loopback, which is also the case where the proxy
refuses to start without a token — see Remote access.
Model metadata
Section titled “Model metadata”contextWindow and maxTokens are emitted only when the catalog reports an authoritative context
window. When it does not, both fields are omitted for that model and Pi applies its own defaults;
ocx export prints how many rows fell into that case.
maxTokens is a schema-satisfying budget of 32000, clamped down to the context window so a
small-context model is never given more output than context. It is not a claim about any specific
model’s true maximum.
Two fields are deliberately absent. cost requires all four price fields and opencodex has no
price data for routed models — emitting zeros would assert that every model is free.
reasoning is the one field that used to be absent and now is not: Pi stores a boolean while the
catalog carries an effort ladder, and mapping one onto the other used to be a guess. Since the
catalog’s ladder is the proxy’s own statement about whether a model accepts reasoning parameters
(adapters honor reasoning_effort), an export row with a non-empty ladder now emits
"reasoning": true, and a row without one (or with an explicitly empty ladder) stays
reasoning-free. Pi then offers its effort control for exactly the models opencodex will accept it
on. The export also emits a thinkingLevelMap that hides every pi level with no declared target
(null), so pi never offers — and never sends — an effort the ladder does not contain. One
fallback keeps the model usable: when ultra is declared without max, pi’s max level maps
to ultra (still a ladder member).
If you need a different mapping, hand-edit thinkingLevelMap afterward as documented by Pi.
Treat reasoning as Pi-UI metadata: it is derived from the catalog ladder, not proof that the
upstream natively supports a reasoning parameter. What the proxy actually sends for a given
reasoning_effort value depends on the provider’s adapter and model — it may pass the value
through, translate it (wire aliases), clamp it to the configured ladder, emulate it, or omit it
entirely (e.g. noReasoningModels). The boolean only controls whether Pi offers the control at
all.
Schema status
Section titled “Schema status”Requirements
Section titled “Requirements”A running opencodex proxy (ocx start) and Pi installed. ocx export reads the live catalog
through the proxy’s management API, so a config can never be emitted with an empty model list.

