Pi extension for Kimi Code

Use Kimi Code in Pi, with the Kimi parts handled.

Pi already has a basic kimi-coding provider. This extension is for the parts that start to matter once Kimi Code becomes part of your real Pi workflow: account login reuse, file uploads, measured cache behavior, live model metadata, and optional Moonshot search/fetch tools.

Why this exists

Pi is a small harness you adapt to your own workflow. Kimi CLI is Moonshot's official Kimi Code path. This package sits between them: Kimi Code as a Pi provider, plus the Kimi-specific details that the basic provider keeps simple.

• Use your Kimi account. Log in with /login kimi-coding, or reuse an existing kimi-cli session.
• Send files the Kimi way. Large inline images go through Kimi's Files API and become ms:// references instead of huge base64 payloads.
• Know what the cache is doing. Kimi caches by content prefix. This repo measures that behavior instead of pretending prompt_cache_key controls it.
• Use the safer protocol by default. OpenAI-compatible mode is the default because tool results are less ambiguous there. Anthropic-compatible mode is still available.
• Turn on Kimi-native tools when you want them. moonshot_search and moonshot_fetch are opt-in, configurable per user or per project.

What this package adds

• Kimi account login in Pi, plus KIMI_API_KEY for CI or pay-per-token use.
• kimi-cli credential reuse from ~/.kimi/credentials/kimi-code.json.
• Kimi Files API uploads for large inline images.
• Live model metadata from Kimi at login / refresh time.
• OpenAI-compatible mode by default, Anthropic-compatible mode on request.
• Kimi K2.6 reasoning level mapping for Pi's reasoning controls.
• Stream cleanup for Kimi's thinking-only placeholder text.
• Optional moonshot_search and moonshot_fetch tools via /kimi-settings.
• No build step; Pi loads the TypeScript extension directly.

Install

From npm:

pi install npm:pi-provider-kimi-code

Or load a local checkout without installing:

pi -e /path/to/pi-provider-kimi-code

Install from GitHub Release tarball

If you prefer not to use npm, download the tarball from the latest release, extract it, and install from the local path:

curl -L https://github.com/Leechael/pi-provider-kimi-code/releases/latest/download/pi-provider-kimi-code.tar.gz | tar -xz -C /tmp
pi install /tmp/pi-provider-kimi-code

Sign in

Inside Pi, run:

/login kimi-coding

A browser tab opens, you sign into your Kimi account, and Pi stores the credential at ~/.pi/agent/auth.json. Tokens refresh automatically.

If you already use kimi-cli, this extension can reuse its credential file:

~/.kimi/credentials/kimi-code.json

The file is read-only from this extension's side. Set KIMI_SHARE_DIR if your kimi-cli share directory lives somewhere else.

For CI or pay-per-token use, set KIMI_API_KEY instead:

KIMI_API_KEY=sk-... pi

Model

This provider publishes one Pi model ID:

kimi-coding/kimi-for-coding

Select it inside Pi:

/model kimi-coding/kimi-for-coding

Kimi keeps Coding models behind aliases. Rather than hardcoding a stale model list, this extension asks Kimi for the current model info when you log in or refresh. If your account is on a newer rollout or internal test, Pi can pick up the latest model name and context size without waiting for a package release.

Fallback values:

• Context window: 262144 tokens
• Max output: 32000 tokens
• Input: text and image
• Reasoning: enabled

Kimi K2.6 supports Pi's reasoning levels. This provider maps them to Kimi's current reasoning efforts:

• off / none — reasoning disabled
• minimal / low — low effort
• medium — medium effort
• high / xhigh — high effort

If Kimi reports a larger context window, the provider uses that value. You can also override the advertised context or model name with KIMI_MODEL_MAX_CONTEXT_SIZE / KIMI_MODEL_NAME; see docs/ENV.md.

Optional Moonshot tools

Kimi Coding has server-side search and fetch tools. This extension can expose them to Pi as:

• moonshot_search
• moonshot_fetch

They are off by default. Turn them on when you want Kimi's own search/fetch path in the agent loop.

Inside Pi, run:

/kimi-settings

That command shows your current Kimi usage summary and lets you edit the home or project config. Changes apply to the active session tool set.

Config files are JSON:

• Home: ~/.pi/pi-provider-kimi-code.json
• Project override: <cwd>/.pi/pi-provider-kimi-code.json

Project config overrides home config with a deep merge. Missing files or missing keys mean both tools stay off.

{
  "tools": {
    "moonshot_search": { "enabled": true, "default_collapsed": true },
    "moonshot_fetch": { "enabled": true, "default_collapsed": true }
  }
}

Both tools require /login kimi-coding OAuth credentials. KIMI_API_KEY is not used for these tools. Your account also needs access to Moonshot's server-side search/fetch services; if not, the upstream service can return subscription or whitelist errors.

default_collapsed controls only the TUI preview. The full tool result still goes to the model; set it to false if you want previews expanded by default.

If you already use another search or fetch tool, pick one path for a session. Overlapping tools can make the model choose the wrong one.

Common knobs

Most users do not need environment variables. Two are worth knowing:

• KIMI_API_KEY — static API key for CI or pay-per-token use.
• KIMI_CODE_PROTOCOL — openai by default; set to anthropic if your Pi setup needs Anthropic-compatible requests.

Moonshot search/fetch tools are configured through /kimi-settings or JSON config files, not env vars.

The full env list, including base URL overrides, kimi-cli path overrides, upload tuning, debug logs, and model metadata overrides, lives in docs/ENV.md.

Notes

Kimi CLI vs Pi

kimi-cli is Moonshot's official terminal agent. Pi is the harness you adapt to your own workflow: extensions, skills, prompts, themes, custom commands, status bars, and UI pieces. This package lets you keep Kimi Code as the model path while staying inside Pi.

Cache behavior

Kimi's cache is content-based. It fires automatically when your prompt prefix matches an earlier request. prompt_cache_key, Anthropic cache_control markers, and identifying headers like X-Msh-Device-Id are all ignored for cache decisions — cache is keyed purely by prompt content and is shared across machines, agent forks, and device-id rotations on the same Kimi account.

See docs/caching.md for the measured behavior: TTL, cross-protocol cache reuse, 256-token prefix alignment, device-id sharing, and the cases that invalidate cache.

Protocol modes

Kimi's coding endpoint speaks both Anthropic and OpenAI dialects. This extension defaults to OpenAI-compatible mode.

KIMI_CODE_PROTOCOL supports:

• openai — default, uses /coding/v1/chat/completions
• anthropic — uses /coding/v1/messages

Use Anthropic mode if your Pi setup depends on Anthropic-style request or tool semantics.

Why OpenAI-compatible mode is the default

The Anthropic-compatible protocol has an awkward tool-result shape: tool output is wrapped inside a role: "user" message. That is valid Anthropic format, but Kimi can sometimes read it like a real user message and continue from the wrong premise in multi-turn tool loops.

The OpenAI-compatible protocol uses a dedicated role: "tool" message, so the boundary is clearer. That is why this extension now defaults to openai. The Anthropic path stays available for setups that need it. See issue #5 for details.

Is this affiliated with Moonshot AI?

No. This is an independent extension. The login flow is derived from the public implementation in the open-source kimi-cli repository.

Troubleshooting

pi reports fetch failed even though curl works

Pi runs on Node's fetch / undici stack, which handles http_proxy / https_proxy / all_proxy differently from curl. Verify those variables in the Pi process's environment. The bundled smoke-test script scripts/test_e2e.sh prints the effective proxy-related environment for easier debugging.

/login kimi-coding prints a device code but the browser never opens

The login flow always prints a verification URL. If your terminal or OS blocks auto-open, copy the URL and paste it into a browser manually.

"Access denied" or subscription errors after a successful login

Your Moonshot account needs an active Kimi Code subscription for the provider to do anything useful. If the same account works in kimi-cli, re-run /login kimi-coding to refresh credentials.

Moonshot tools do not show up

Run /kimi-settings and check whether moonshot_search / moonshot_fetch are enabled in the home or project config. These tools also require /login kimi-coding; KIMI_API_KEY is not enough.

If you changed the JSON config by hand, reload it through /kimi-settings or start a new Pi session.

Moonshot tools return subscription or whitelist errors

The tools call Moonshot's server-side search/fetch services. Some accounts may not have access even with an active Kimi Code Plan. The error comes from the upstream service.

Large images fail with a payload error

This extension uploads images over KIMI_CODE_UPLOAD_THRESHOLD_BYTES (default 1 MB) to Kimi's Files API and references them as ms://. Set KIMI_CODE_DEBUG=1 to see upload decisions in the provider logs.

Prompt cache never seems to hit

Kimi's cache is content-based: it fires automatically when your prompt prefix matches an earlier request, independent of any explicit cache key. If cache_read_input_tokens (Anthropic) or cached_tokens (OpenAI) stays at 0 across calls, something in the prompt is varying between turns. The usual suspects:

• On the Anthropic-compat endpoint, the system prompt or the tools array changed (e.g. an extension changed the tool set mid-session). Either fully invalidates the cache — see docs/caching.md, Finding 11. OpenAI-compat endpoint not yet measured for this scenario.
• An image_url reference (ms://<file_id>) changed between turns. Same rule — see Finding 17.
• You're comparing across two cold pi invocations, not within a single session. Cache benefits accrue within a session; Pi's system/tools assembly drifts between sessions. See Finding 18.
• A timestamp, request ID, or randomized header is being interpolated into the prompt.
• The first ~256 tokens of the prompt differ between turns.

PI_CACHE_RETENTION=none skips prompt_cache_key injection but does not disable Kimi's caching (the cache is unconditional). For deterministic measurement, run scripts/test_e2e.sh with KIMI_E2E_ONLY_CACHE=1. See docs/caching.md for full mechanics.

OpenAI-compatible tools complain about a developer role

In OpenAI mode this extension maps the developer role to system (Kimi's Coding endpoint does not recognize developer). If something in your toolchain expects developer to round-trip, use Anthropic mode instead.

References

• Pi: earendil-works/pi
• Upstream login implementation and feature request: MoonshotAI/kimi-cli · kimi-cli#757
• Environment variables: docs/ENV.md
• Testing guide: docs/TESTING.md
• Cache behavior: docs/caching.md
• Architecture notes: docs/architecture.md

Credits

Based on the login implementation from kimi-cli by Moonshot AI. Built as a Pi extension by @badlogic.

License

MIT