jusi-acp

jusi-acp is the shared Agent Client Protocol family for Jusi 1.0. It gives independently installed ACP agent providers one %%acp notebook experience: structured VisiData events, durable follow-ups, exact cancellation, permission choices, client-owned command execution, session controls, completion, and editor-native copy/open/diff actions.

This package is a family library, not an exact provider. Installing it alone does not add a Jusi catalog entry. An exact package such as a future jusi-gigacode depends on jusi-acp and supplies its own catalog entry, attesting kernel module, launch validation, and worker factory.

Configuration

Jusi loads ~/.jusi/jusi.toml at the kernel target. ACP uses the standard [magic.alias] layout:

[acp.work]
provider = "gigacode"
path = "/work/project"
additional_directories = ["../shared"]
model = "provider-owned-model-name"

provider, path, additional_directories, and mcp_servers are common family keys. The selected exact provider validates the complete table and owns the remaining keys. Configuration is frozen for one notebook runtime; use a full Jusi restart to reload it.

%%acp work
Inspect the project and implement the requested change.

Resume syntax is explicit:

%%acp work --load SESSION_ID
Continue after replaying agent history.

%%acp work --resume SESSION_ID
Continue without requesting history replay.

To browse sessions without putting an ID in the magic header, start a cell with:

%%acp work
/sessions

Enter on a session loads its history into the turns sheet. Later Jusi follow-ups continue that selected session. Press q from the turns sheet to return to the sessions list and select another session. While loading, follow-ups and further selections are rejected with a wait message. A failed load preserves the previous session and its displayed history. The agent must advertise session/list and either session/load or session/resume.

Attention

Approvals and questions publish persistent Jusi attention. Answering, declining, cancelling, or withdrawing the request clears it. Pressing q only closes its view; a reopens the active request. Multi-step questions update the same badge.

Background completion notices require a live tool reported as in_progress when its original turn ends, followed by a completed or failed update for that same tool ID. Qwen/GigaCode's explicit background_task_completed and background_notification message metadata also trigger notices for completed or failed tasks, even if the launching tool already finished. Notices are deduplicated by task ID and, when supplied, the originating tool ID across both event types. Each qualifying job produces one notice, including when a newer turn is running. Ordinary messages, normal turn completion, foreground tools, and replayed history produce no notices. Message text alone cannot trigger a completion notice.

Use :JusiAttention to visit pending clients and :JusiAttention! to dismiss completion notices. Notifications do not move editor focus. Summaries omit prompt and tool content. Delivery failures are recorded in ACP diagnostics and do not block the agent or answers; uncertain creation is not retried.

This requires Jusi core 1.0.5 or later and the matching Neovim plugin. Exact providers using family_claim() inherit the attention capability. Providers with copied catalog claims must add it too; Jusi rejects conflicting capability lists for the same family.

Exact provider integration

The exact package advertises the shared claim and wraps its identity around the family kernel adapter:

# catalog.py
from jusi_acp import family_claim

def catalog_entry():
    return {
        "plugin_id": "gigacode",
        "plugin_version": __version__,
        "distribution": "jusi-gigacode",
        "families": [family_claim()],
        "kernel_extensions": ["jusi_gigacode.kernel"],
        "worker_entry_point": "jusi_gigacode.worker:create_worker",
        "media_types": ["text/x-ansi"],
        "interaction": "terminal_interactive",
    }

# kernel.py
from jusi_acp import KernelProviderAdapter

_adapter = KernelProviderAdapter("gigacode", __version__)
jusi_kernel_adapter_v1 = _adapter.manifest
configure_jusi_runtime_v1 = _adapter.configure
load_ipython_extension = _adapter.load_ipython_extension

# worker.py
from pathlib import Path
from jusi_acp import ACPWorker, AgentLaunch, ProviderSpec

def resolve_launch(config, cwd: Path):
    return AgentLaunch(("gigacode", "--acp"), cwd)

PROVIDER = ProviderSpec("gigacode", __version__, resolve_launch)

def create_worker(context):
    return ACPWorker(context, PROVIDER)

The provider must use the same ID and version in its catalog, kernel adapter, and ProviderSpec. It must not register %%acp itself or store live sessions globally.

Shared behavior

• ACP v1 over the official Python SDK.
• Python 3.10 or newer.
• execute, followup, complete, interrupt, and editor_actions for every exact provider claiming the family.
• Markdown syntax and indentation in ACP prompt cells.
• ACP terminal methods run bounded, non-interactive subprocesses at the target.
• ACP filesystem and terminal-auth capabilities are not advertised.
• Form and URL elicitation are supported using the published v1 SDK. The SDK classifies these routes as unstable; this does not enable ACP v2 or require a Git dependency.
• Agent-driven authentication is available through /auth METHOD_ID or an exact provider's configured AgentLaunch.auth_method.
• /sessions, /model, /mode ID, /config ID VALUE, and /cancel are family commands.
• /model opens an advertised-model picker. Enter switches the session model through ACP and closes the picker; q cancels. No conversation turn is added.
• Initial bodies and later follow-ups use the same family-command dispatcher.
• ACP available_commands_update entries appear in completion and in the event sheet with their descriptions and optional free-text input hints. Invoking an advertised slash command other than a family command sends its complete text as a regular ACP prompt; command-specific behavior and output remain agent-owned.
• Press d on a tool event to open its ACP-provided diff. Press d on a turn to browse all files changed during that turn, then Enter to open one through Jusi's acknowledged, remote-safe read-only Vim diff action. Continuous edits to one path are composed; discontinuous revisions remain separate.
• ACP remains authoritative for conversation context. The family stores a normalized read-only presentation cache so resume-only sessions retain useful review history.
• The live event view groups adjacent assistant and thought chunks, consolidates tool updates by call ID, and updates terminal output in place while retaining every raw ACP update in the durable journal.
• Completed prompts appear as one row each in a turns sheet. Enter opens that turn's grouped event view. Completion selects that turn and opens its last assistant message as a wrapped VisiData text sheet. Close it with q to return to the selected turn. Notebook focus stays where it is; a new prompt replaces the automatic preview. Pending questions take priority.

The first turn begins inside the terminal application after Jusi creates the client. It is cancellable with the application's c command or /cancel, but is not published as a Jusi client operation. Later follow-ups are exact Jusi operations and support :JusiInterrupt without closing the session.

Development

python3.12 -m venv .venv
.venv/bin/pip install -e '.[dev]'
.venv/bin/pytest

The notebook follow-up integration test uses a sibling jusi frontend checkout, or the path supplied in JUSI_NVIM_ROOT, together with the installed Python backend. It edits notebook cells through Neovim and checks the real serialized follow-up lane, answer history, and same-client reuse.

Turn review and questions

The turns sheet records the model ID reported by the agent, from either model configuration or older ACP session model metadata. It stays blank when the agent does not report a model; it is not inferred from the executable name. Tool events show the tool name/kind, command, and raw input when supplied. The reply column contains the final agent message from each turn, and changes counts paths for which the agent supplied ACP diff content. Enter opens the full event details. An empty changes view means the agent supplied no diffs; it does not prove that no files changed.

Usage is presented by the ACP family whenever the agent reports it. The turns sheet shows total_tokens, input_tokens, output_tokens, thought_tokens, cached_read_tokens, and cached_write_tokens from the final prompt response, plus the latest context_used, context_size, cumulative session_cost, and currency from ACP usage_update notifications. Zero is displayed as zero; unreported values stay blank, and a new turn does not inherit old usage. These snapshots survive presentation-cache reloads. Enter on a turn opens its events; Enter on a usage or stop event exposes the original payload and metadata. Usage columns follow the existing turn review columns; scroll horizontally to see the full breakdown.

Context usage is the number of tokens currently in the context window, not tokens consumed by a turn. Cost is cumulative for the session. Final response token usage is experimental and is displayed exactly as reported: ACP's usage scope ambiguity means agents may report per-turn or cumulative token counts. The family does not sum them or infer deltas. Provider-specific usage hidden in extension metadata needs an explicit provider mapping; arbitrary metadata is preserved without guessing its meaning.

Qwen/GigaCode question requests carried in rawInput.questions pause the agent and show the current question and choices in a read-only view. Type your answer in the notebook cell in Vim and submit it using the usual Jusi follow-up action. Each follow-up answers one question. Write the option label (available in cell completion) or any free-form, multiline answer; text and whitespace are preserved. For multiple-choice questions, describe all your choices in the answer. An empty answer is rejected without advancing to the next question.

When a question arrives, the current Jusi operation returns successfully with status: awaiting_answer, freeing the follow-up lane while keeping the ACP request pending. After the last answer, that same ACP turn resumes, and the answer follow-up stays active until the turn finishes or asks another question. Answers remain in the original turn's event history and in normal Jusi follow-up history; they never become separate agent prompts. Once the turn finishes, the next follow-up starts a new prompt unless a session request is still pending. Requests can arrive after prompt completion and remain answerable until resolved or cancelled; prompt completion alone does not cancel them.

Submit /cancel from the cell to cancel a waiting turn, including any partially answered question set. Closing the question view just hides it; it does not answer or cancel anything. While waiting, all other cell text is an answer, including slash-prefixed text. During resumed work, use :JusiInterrupt as usual. While waiting for input there is no active Jusi operation to interrupt, so use /cancel (or c in the question view). No text entry in VisiData is required.

Ordinary tool permission requests retain their approval choices, with d exposing the full request payload. Questions use the Qwen permission extension, not generic ACP elicitation.

ACP UI updates run from the drawing thread with a bounded curses polling interval, including while the terminal has no focus. Recoverable SDK protocol errors stay in event diagnostics; runtime failures use VisiData's Ctrl-E error history. Agent stderr appears as labelled diagnostic events, including during authentication. Browser launcher environment variables are preserved, and provider environment overrides take precedence.

Qwen's qwen/notify/session/prompt-suggestion notification is accepted as an advisory Suggested follow-up journal event. It never submits a prompt or edits the notebook, and does not replace the completed turn's reply. Suggestions stay inside the originating turn's event sheet, including when received after the turn ends. Qwen's session prompt counter routes a delayed suggestion even while a later prompt runs; agents omitting that ID use the current or latest turn.

To collect the last ten saved ACP diagnostics on the target machine, run python -m jusi_acp.diagnostics using the same Python environment as Jusi. It prints package versions and diagnostic messages, including the method and parameters of a failed notification when captured. Check that output before sharing it: agent-supplied notification parameters may contain private data.

Session activity on ACP v1

The default sheet remains prompt-centric: one row per user prompt, with Enter for its grouped events and Ctrl-O on a cell for the usual Vim representation. Known tool, terminal, and message IDs route late updates to their original group, even while another prompt runs. The updates column counts late updates; opening the turn clears its indicator. A message ID is only correlated after its first appearance; its value is never interpreted as a turn identifier.

Events arriving idle without a known owner appear together in an Unassigned session activity row between prompts. Enter opens that group. During a prompt, otherwise uncorrelated events are grouped by their arrival during that prompt; this is presentation context, not proof of worker ownership. Raw updates remain available in the journal. No worker identity is inferred from message wording or arbitrary extension metadata.

From the turns, events, or reply views:

Key	View
p	Current session plan
P on a turn	Plan revisions received in that turn
t	Client-owned terminal monitor; Enter opens live output
w	Pending requests in arrival order; Enter previews without retargeting answers
a	Return to the active full-screen question

/plan, /terminals, and /pending also open these views from a follow-up when no question is waiting. Closing a view does not stop work. Terminal output follows the end while you are at the bottom; scrolling up keeps your position. Output limits and truncation indicators come from the client terminal service. Commands run internally by the agent do not appear here unless it uses ACP terminal calls.

Each standard plan update replaces the current plan in full, including an empty plan. Historical snapshots stay with the turn or unassigned group where they arrived. ACP v1 does not supply standard task/plan identities for independent worker plans, so the client presents one current session plan.

Pending requests and elicitation

Questions, approvals, and elicitations share one FIFO queue. A request containing several questions keeps its place until those questions are answered. The main view shows the full current question; its title shows the source and the number of other queued requests. Later arrivals do not replace it or reset scrolling.

Elicitation is an agent request for user-provided information. Form elicitation uses the same follow-up flow for free text. Short structured fields have an editable value cell: e edits it and Enter submits it. They can also be answered from the notebook. Booleans use true/false, numbers use JSON numbers, and multi-select fields use a JSON array of strings. Invalid answers leave the same field active. Optional fields support /skip, supplied defaults support /default, and /empty supplies an empty string. /decline declines an elicitation; /dismiss cancels only that elicitation. URL elicitation displays the URL for you to open; Enter or /accept acknowledges it without claiming that external work is complete. Agent completion notifications are recorded separately.

If the active request is withdrawn, further answer text is rejected rather than sent to the next request. Submit /next to acknowledge the withdrawal and show the next question. /cancel still cancels the session's pending requests and active prompt. There are no additional Vim answer buffers.

Project path completion

In a live ACP cell, type @ and invoke normal Jusi completion (Tab). For example, Explain @ offers files and directories at the project root. @src/ offers only the immediate children of that directory; select a directory to continue browsing one level at a time. Selecting a candidate preserves the @, for example @src/jusi_acp/application.py. No file is attached or read into the prompt by completion. Paths beginning ./ or ../ continue to complete, and spaces are backslash-escaped. Other prompt text, including text after the cursor, is preserved. Completion also works while answering questions.

The target-side session working directory and configured additional directories are searched. Git projects respect Git ignore rules for untracked files; tracked files remain available. Outside Git, common generated directories are excluded. Results are bounded and cached briefly so completion does not scan on every key.

Jusi currently requires a live client before completing a plugin cell. To complete your first prompt, execute an empty %%acp ALIAS cell first, then write the prompt as a follow-up. No agent prompt is sent by that empty initialization.

See the manual testing guide for prompts and expected behavior, including features that depend on what the agent actually reports.