thwip

Universal Coding Agent Multiplexer

Discover supported local AI tools, connect configured model providers in one terminal interface, and switch providers while preserving completed text conversation history.

Features

• Auto-Detection: Discovers installed AI coding agents (Claude Code, Antigravity CLI, OpenAI/Codex, Aider, Copilot, Cursor, Windsurf, Cline, Ollama) and configured credentials.
• Existing Sign-ins: Chats through installed Codex, Claude Code, and Antigravity CLIs using their own logins and live model lists, with no API key required.
• Context Portability: Switch providers with stored conversational text. Working files remain in the selected local project; they are not automatically uploaded.
• Handoff Preview: Inspect text continuity, omitted state, capability changes, approximate context pressure, and a text fingerprint before switching. Runs locally without model calls.
• Dynamic UI: Terminal interface adapts its status bar, capabilities, and theme based on the active provider.
• Capability Disclaimers: Highlights when an agent lacks specific capabilities such as file editing or code execution.
• Rate Limit Failover: Detects HTTP 429 errors or quota exhaustion and prompts instant switching to ready fallback models.
• Tool Layer: Shared file editing, code execution (Python, Node, Shell), and Git integration across connected models.
• Session Persistence: Save and resume sessions across projects with /session save and /session load.
• Familiar Flow: The same everyday commands as Codex, Claude Code, and Antigravity (/model, /new, /resume, /compact, /diff, /copy, !cmd, @file), plus autocompletion, Ctrl+S / Ctrl+T shortcuts, and streaming Markdown.
• Project Memory and Second Brain: One context.md per project that every agent reads and maintains, filed into your Obsidian vault with cross-project links by stack, area, and tag.
• Live Model Lists: Model catalogs come from the connected CLI or the provider's list-models endpoint, never from a hardcoded list.

Quickstart

1. Installation

Install the published package:

pip install --upgrade thwip-cli

Or install the repository in editable mode for development:

git clone https://github.com/tanmayhutt/thwip-cli.git
cd thwip-cli
pip install -e .

2. Launching thwip

Start the interactive terminal in your current project directory:

thwip
thwip --project ~/code/my-app   # open a specific project
thwip --version
thwip man                       # read the manual page
thwip install-man               # then `man thwip` works

Slash Commands and Shortcuts

Short aliases are available for frequent commands: /a, /m, /s, /sw, /k, /g, and /t.

Existing CLI sign-ins (no API key needed)

If Codex, Claude Code, or the Antigravity CLI is installed and signed in, Thwip connects to it at startup and uses that sign-in for chat. No API key is copied or required, and Thwip never reads the CLI's stored credentials. A configured direct API key for the same provider always takes precedence over the native connection.

/models refreshes the catalog supplied by each CLI. An explicit model ID that is not in the catalog is passed to the CLI for validation instead of being rejected by a bundled list. A model available in a desktop app may still be absent from the installed CLI's catalog or account access.

Each provider keeps a warm native session. The first message to a provider sends the portable conversation once; after that only new messages are sent. Codex keeps one app-server process running and resumes its thread; Claude Code uses --session-id and --resume; Antigravity uses --conversation. When you come back to a provider after chatting with another one, it receives a short catch-up block containing only what it missed. The native session IDs are stored in the thwip session file next to the transcript, validated on load, shown by /status, and cleared by /new, /clear, /compact, and a project change. If a CLI can no longer continue a session, thwip says so and resends the full conversation to a fresh one.

Native connections are read-only by default. Codex starts with a read-only sandbox and asks before operations outside it; approval requests appear in Thwip with the command or file list and default to denial. Claude Code and the Antigravity CLI run in their non-interactive print modes, where tools that would need an approval are declined by the CLI itself. Each turn sends the portable text conversation to a fresh native session, so native reasoning and tool state do not carry between turns. Ctrl+C interrupts the current turn and stops the child process; the unanswered message is removed so it can be re-sent or handed to another provider.

Native billing and usage limits are managed by each CLI account. Thwip records the token counts the CLIs report but does not estimate cost for them. Codex and Claude Code also report their account usage windows (5 hour and 7 day) after each response; /limits and /status show the used percentage and reset time. When a CLI reports an exhausted usage limit, the standard failover prompt offers the other connected providers.

/native codex remains available as a launcher: it saves the Thwip session and replaces Thwip with the Codex CLI itself in the selected project. Conversation history is not transferred by the launcher; use /session load after restarting Thwip to resume.

What the assistants are told

thwip imposes no persona. Every assistant receives, in this order: your own standing instructions if you set any, a short neutral note from thwip ("you are being used through thwip; earlier turns may have been answered by a different assistant; treat them as real history"), a line about thwip's tools only when thwip is actually offering tools (direct API models), and the relevant parts of the project memory. Native CLIs keep their own system prompts, tools, and safety rules; thwip's note is layered on top and says so.

/prompt                      show what is sent
/prompt set <text>           your instructions for this session, for example "Answer in Hindi" or "I am new to programming"
/prompt save                 keep them in ~/.thwip/config.toml under [defaults] system_prompt
/prompt reset                clear them

Project memory and your second brain

Every project gets one canonical memory file, context.md in the project root, that every agent you use through thwip reads and helps maintain. It records the snapshot, current work (Now, Blocked, Next), architecture notes, decisions, known issues, and dated recent changes. Whichever provider you switch to receives it as instructions, so the project's state survives agent switches and sessions, not just the conversation.

On first run thwip offers to connect a second-brain vault: it detects vaults registered with the Obsidian desktop app, or creates a new Markdown folder. In the vault each project gets a stable index card under Projects/, hub notes under Stack/, Areas/, and Tags/, and a Projects.md dashboard. Projects that share a stack, area, or tag link to each other through those hubs and a "Related projects" list on every card. thwip only writes notes it created itself (marked generated_by: thwip); hand-written notes are never touched.

How the memory reaches the model. The file is split into sections at its headings. The head (frontmatter, Snapshot, Current Work) always goes. The rest is ranked against your current message with BM25, the keyword-ranking formula used by search engines, and the best-matching sections are added within a character budget. A warm native session is only sent sections it has not already seen, as an excerpt attached to the message. Nothing is truncated from the top any more; a note says how many sections were left out so the model can ask. No embeddings, no vector database: at a few dozen sections per project that would add a dependency without adding recall. The memory-deep-recall evaluation task measures this against the old first-8,000-characters behaviour (python -m thwip.evals --memory truncate).

When you /quit after a real conversation, thwip offers the update once. Settings live under [memory] in ~/.thwip/config.toml:

[memory]
enabled = true
file = "context.md"                  # memory file name in each project root
vault = "/Users/you/Obsidian/Brain"  # chosen at first run; empty means no vault
offer_update_on_quit = true
cards_dir = "Projects"               # vault subfolder for thwip's notes
scan = ["/Users/you/code"]           # folders whose subfolders are projects, for /memory sync all

If your vault already has hand-written project notes under Projects/, set cards_dir to a subfolder such as Projects/thwip. thwip's cards, hubs, and dashboard then live inside that folder and link among themselves, and your own notes stay untouched.

Evaluation harness

thwip.evals runs a fixed set of tasks against any adapter and scores them deterministically: pass or fail, latency, tokens, estimated cost, tool calls, malformed tool calls. The same tasks run against an in-process fake adapter, so the scoring code is itself tested offline and in CI.

python -m thwip.evals --list                 # the task set and the source file each task exercises
python -m thwip.evals                        # offline, against the fake adapter; exit code 1 on any failure
python -m thwip.evals --provider broken      # a deliberately bad adapter, to see failures reported
python -m thwip.evals --provider all --out evals.json   # every ready provider, results saved as JSON
python -m thwip.evals --provider openai --task tool-read-file

Each task names the file it tests: the streaming event contract in agents/base.py, exact instruction following, a tool round trip and the path guard in tools/, the consistency of the OpenAI and Anthropic tool schemas, deep recall from a long project memory file, recall across a provider handoff, recall after compaction, a real file edit, honesty about a missing file, recall of archived turns, a schema-valid structured summary, and the compaction worker rule. Thirteen tasks in total. Native CLIs bring their own tools, so for them the tool tasks score the final answer only and say so in the note.

Live model lists

Model lists are not hardcoded. Each connected source supplies its own list:

• Installed CLIs report their models (Codex model/list, agy models, Claude Code aliases). An ID the CLI does not list is rejected; Claude Code additionally accepts full claude-... names because it has no list endpoint.
• Direct providers with a key are queried through their list-models endpoint (OpenAI, Anthropic, Google, DeepSeek, Groq, OpenRouter) at startup, on /models, and right after /key. Non-chat models (embeddings, speech, image, moderation) are filtered out. Context sizes and prices are taken from the provider when it publishes them.
• A small bundled list per provider remains only as an offline fallback and is labelled "bundled fallback" in /models until a key or connection is available.

Endpoint overrides

Any direct adapter can be pointed at a different server: a proxy, a self-hosted gateway, a local test double, or an OpenAI-compatible service. Set an environment variable or an [endpoints] table in ~/.thwip/config.toml. Keys stay provider keys.

export THWIP_OPENAI_BASE_URL=https://gateway.example/v1      # also DEEPSEEK, GROQ, OPENROUTER
export THWIP_ANTHROPIC_BASE_URL=https://gateway.example
export THWIP_GOOGLE_BASE_URL=https://gateway.example

[endpoints]
openai = "https://gateway.example/v1"

The repository uses this to run every direct adapter end to end against a local fake provider in tests/fake_providers.py, so streaming, tool rounds, live catalogs, and HTTP 429 handling are verified through the real SDKs without spending on real keys.

Compaction and early warnings

Two different limits, two different protections.

Context window. When the conversation's estimated size reaches compact_at_percent of the active model's window (65 percent by default; models that publish no window are assumed to have assumed_context_tokens, 200,000), thwip offers to compact. Compaction summarises the older turns and keeps the last keep_recent_messages (4) word for word. The summary is written by a ready provider other than the active one, because the provider that is running out of room or quota is the one that cannot be trusted with one more request; the active provider is used only when nothing else is connected, with a warning. /compact does the same on demand. The transcript on disk is never deleted. Every provider's warm session restarts from the compact history on its next turn.

Usage quota. Codex and Claude Code report their 5-hour and 7-day usage after each turn. When a window reaches quota_warn_percent (85 percent by default) thwip warns once per window and names the ready alternatives, so you can switch before the limit hits rather than after. Antigravity reports no windows, so for it the first signal is still the limit error, which failover handles.

[limits]
quota_warn_percent = 85
compact_at_percent = 65
assumed_context_tokens = 200000
keep_recent_messages = 4

The evaluation harness covers both: compaction-recall checks a fact from early in a long conversation survives summarisation, and compaction-worker-never-active checks the worker rule.

Benchmark

Published at https://thwip.tanmaytiwari.me/#benchmark and stored under docs/benchmark/. Thirteen tasks against the three signed-in CLIs on one machine, 2026-10-04, run twice (home Wi-Fi, then a phone hotspot) with identical pass/fail results:

What failed, honestly. Codex reads a file outside the project with its own shell tools: its read-only sandbox permits reads anywhere and auto-approves them, and no setting thwip can pass changes that. Claude Code used to do the same; since v1.14.0 thwip confines its read tools to the project with permission patterns (Read(./**), Glob(./**), Grep(./**)), verified live, so the path guard now holds for direct API models and Claude Code. Antigravity returned empty answers twice: its print mode auto-denies any tool that needs a permission prompt and returns nothing, explaining itself only on stderr; thwip surfaces that explanation. Antigravity's latency is its own per-turn work, not the network: 54 s on home Wi-Fi, 51 s on the hotspot; a kept-open process was tried and cut a turn to about 20 s but still carried 18 s of overhead and hung on the third turn, so it was not adopted. The file-edit task is not applicable to native sessions because thwip runs them read-only.

Recall, structured outputs, tracing, guardrails

Recall. Compaction archives the older turns inside the saved session instead of discarding them. When a later message refers to something archived, the matching turns are attached automatically as an excerpt (ranked with the same BM25 code as project memory), /recall <words> searches them by hand, and direct API models get a search_history tool. Nothing you said is ever out of reach.

Structured outputs. Compaction summaries are requested as JSON matching a schema (context, decisions, open tasks), validated, and repaired by re-asking with the exact problem, up to two times, before being rendered to Markdown deterministically. If a model cannot produce valid JSON the plain-text summary is used and thwip says so. Code: structured.py.

Tracing. Every request writes one line to ~/.thwip/traces.jsonl: provider, model, kind (chat, compaction, eval), latency, tokens, estimated cost, tool calls, error. Measurements only, never text. /trace [n] shows the recent records and a per-provider summary.

Output guardrails. Before an answer is stored, strings shaped like API keys, tokens, or private keys are masked and you are told; an empty answer is reported instead of silently saved. Code: guardrails.py.

Continuous integration. Every push runs lint, the test suite, and the offline evaluation harness on Python 3.11 and 3.13; a failing task fails the build (.github/workflows/ci.yml).

Usage-limit failover

When the active provider reports an exhausted limit (Codex "You've hit your usage limit", Claude Code "usage limit reached" or a rejected rate-limit event, Google RESOURCE_EXHAUSTED, or HTTP 429 from a direct API), Thwip stops, shows the ready alternatives with their default models, and offers to switch. Accepting switches the provider, keeps the text conversation, and re-sends the unanswered message. Set [limits] auto_switch = true to skip the question. The [fallback] chain order is honored; a chain model the provider does not list falls back to that provider's default.

Auditable handoffs

/handoff
/handoff google
/handoff openai gpt-5.6-terra

/handoff previews the current target; specifying a provider uses its default model unless you supply a model ID. Targets can be inspected without credentials or an installed provider. /switch shows the same report before changing the active agent.

The report includes:

• Exact counts of transferred user/assistant text messages and excluded stored records.
• A count of observed transient tool results that are not in portable history. New sessions track from creation; older saved sessions explicitly report partial coverage.
• Capability gains and losses using the local model catalog.
• Approximate request size including tool schemas, with up to 4,096 tokens reserved for an answer in the advisory calculation. This does not change generation settings.
• SHA-256 of canonical system-prompt and conversational-text JSON. It stays the same across targets when that text is unchanged. Tool schemas and attribution metadata are intentionally outside this text fingerprint.

The preview makes no model requests, saves no transcript exports, executes no tools, and does not trim or summarize history. Token sizing uses UTF-8 bytes divided by four plus per-message overhead, not a provider tokenizer. Catalog limits can be stale; an apparently fitting request can still fail. Warnings are advisory, not switch gates. Hidden reasoning and provider-native state do not transfer. The digest proves neither delivery nor semantic understanding, and is not a signature or privacy guarantee.

See research and prior art for the differentiation rationale.

Supported Companies and Agents

Configuration (~/.thwip/config.toml)

thwip auto-detects existing API keys from environment variables and existing agent configs (~/.claude.json, ~/.gemini/config.json). Configuration can also be set manually:

Installed CLI sign-ins and API access are separate paths. A signed-in Codex, Claude Code, or Antigravity CLI is used directly through its own protocol (see above). The direct SDK adapters for Anthropic, Google, OpenAI, DeepSeek, Groq, and OpenRouter require a provider API key. Ollama needs no key when its local server is running.

[defaults]
agent = "claude"
model = "claude-opus-5"
project = "."
theme = "dark"
stream = true
auto_save = true
confirm_tools = true

[keys]
anthropic = "sk-ant-..."
google = "AIza..."
openai = "sk-..."
deepseek = "sk-..."
groq = "gsk_..."
openrouter = "sk-or-..."

[ollama]
host = "http://localhost:11434"

[fallback]
enabled = true
chain = [
    "claude/claude-opus-5",
    "google/gemini-3.7-flash",
    "openai/gpt-5.6-terra",
    "deepseek/deepseek-v4-flash",
    "ollama/llama3.3"
]

Prefer /key <provider> over editing the file directly. Mutating workspace tools ask for confirmation by default, file access is restricted to the selected project, and Thwip stores its config and saved sessions with user-only permissions.

License

MIT License