graphban-fleet

The fleet supervisor: a thin local client that runs where the agents actually run. It spawns vendor CLI processes holding seats the Graphban server issued, and it reaps them. Ships as graphban-fleet, with a gbfleet entry point.

Specified by PRD-22.

Two servers, and only one of them has authority

Arbitration is remote and authoritative; process control is local and unprivileged. A planner attaches both:

planner (a terminal, or an in-session orchestrator)
 ├─ graphban   (remote HTTP)  → mint_enrolment, propose_allocation, assign_role, fleet_status
 └─ gbfleet    (local stdio)  → spawn, stop, ps, orphans

gbfleet runs on the developer's machine and the Graphban server never learns its calls happened. There are no HTTP routes on the local surface. Authentication there is process ownership — the planner speaks over a pipe to a child it launched — not a credential.

The supervisor holds no authority of its own. It can only launch a process holding a seat the server issued, to do work the server arbitrates. Delete it and every invariant still holds; the fleet just needs a human to open terminals again. It is explicitly not a security boundary (PRD-22 D-k): a compromised vendor binary has whatever the user has, and the worktree is a blast-radius convention, not a sandbox.

Why it is in this repository, and not inside backend/

Not a second repository, because the client↔server contract has no schema anywhere — the enrolment code format and its TTL, register_agent's return shape, independent()'s seat semantics, the directive envelope. All of it is changeable in a single PR here, and a cross-repo break would present as absence reading clean: the fleet still spawns, nothing errors, review stops being independent.

Not inside backend/, because graphban-api pulls fastapi, sqlalchemy, pgvector, psycopg, alembic, redis and cryptography, and a laptop running four vendor CLIs needs none of them. tests/test_packaging.py derives its forbidden-dependency set from the backend's own list, so that separation is checked rather than asserted.

Licence — Apache-2.0, deliberately not the repository's FSL-1.1

The repository is FSL-1.1-Apache-2.0. This directory is Apache-2.0, and the divergence is a decision (PRD-22 §8), not an oversight:

• The supervisor is not the moat. It is inert without a Graphban server and holds no authority. FSL's Competing Use clause protects the server; it protects nothing here.
• Adapters are the contribution this component most wants, and they come from people who use other vendors' tools. A non-OSI licence is friction aimed at exactly that audience.
• It is a laptop-installed developer CLI, which is precisely the kind of dependency that meets a corporate licence policy scanner.
• FSL-1.1-Apache-2.0 already commits to Apache-2.0 on a two-year delay. This brings that grant forward for the one component least worth protecting.

If this component is ever extracted to its own repository — the stated trigger is outside contributors who should not hold commit access to the server — extract the adapter interface only, not the supervisor.

Install

uv tool install graphban-fleet

That gives you gbfleet and gbagent — the coding agent is an entry point of this package rather than one of its own, because the supervisor resolves it on PATH like any other vendor binary. uv tool update-shell once if uv says its bin directory is not on your PATH, and uv tool upgrade graphban-fleet to move it forward.

gban, the client for a human at a terminal, is uv tool install graphban-cli — a separate package because it installs on laptops that never run a wave and pulls no dependencies at all.

To run an unreleased change:

uv tool install "git+https://github.com/asc-me/graphban.git#subdirectory=fleet"

Releasing is docs/releasing.md: the tag names the package, and the workflow refuses a tag whose version disagrees with the pyproject.

Running it

One wave, deterministically — you mint the seats, it spawns and reaps:

GBFLEET_API_KEY=... gbfleet up \
    --server https://cloud.agentldgr.dev --seats-file seats.txt --adapter claude

A seats file is one enrolment code per line. A line may also bind the seat to an item (WORKER-7F3K item=GRPH-755 — the child gets the BOUND instruction and claims that item at registration, PRD-36). Both are what until says when it mints a seat itself; here you say them. A mistyped token refuses the whole file before any worktree is cut, and doctor --seats-file refuses it the same way.

These are the two supervision modes PRD-39 D-e names, and the cheap one is the default. deterministic — gbfleet up with the seats you minted, or gbfleet until, which mints just in time and stops when there is no ready work, no unsigned review and no live lease — runs the wave with no LLM in the loop. driven is the escalation: a planner holding this local server beside the remote one, a frontier context polling and adjudicating bounces for the length of the wave. doctor prints which one you are set up for.

Choosing what a wave works on

until drains the project unless you scope it. --prd <id> is the lever:

gbfleet until --repo . --server <url> --project <id> --adapter <vendor> --prd GRPH-P39

Without it, every ready item in the project is fair game — and parking work in backlog is not a defence, because backlog is claimable by design so a crashed agent's item gets offered again. There is no lever in the item shape either: Item has no type column, so an "epic" is a convention in a title and invisible to the claim path. Scoping the wave is the only lever there is (GRPH-797).

--prd scopes the child's credential, not only this loop's choices. The seat each child registers on is minted for that PRD, and the server filters every self-claim path against it — claim_cluster, next_cluster, claim_next and claim_review (GRPH-827). This paragraph used to say that bound seats already achieved this. They did not, and a measured wave says how much they did not: --prd SA-P11 delegated three items, all inside the PRD, and the children then self-claimed six more, none of them in it — including an ops item whose checklist mutates production, which sits top of the queue on score. A worker declined that one on its own judgment. Judgment is not a control, and a README claiming the containment does not create it.

Two consequences worth knowing before you use it:

• --prd cannot be combined with --seats. A pre-minted seat carries no scope, so the wave would report as scoped while those children could claim anything. Refused up front.
• Work with no PRD is unreachable by a scoped wave, for building and for review. Most bug reports have no PRD. Until a second scope axis exists (GRPH-828), the choice is a scoped wave or a reachable backlog, and it is yours to make knowingly.

--prd refuses a server that does not support it. An older Graphban does not reject an unrecognised prd_id — it drops the property and answers the unfiltered question, so the flag would drain the project while reporting the wave as scoped. Before the first spawn, until asks for a PRD that cannot exist: a server that filters returns nothing, one that ignores the argument returns the project, and the second refuses the run naming what it would otherwise have done (GRPH-800). It then reads the tool manifest and refuses again if delegate takes no scope, because a server can filter the divvy and still mint unscoped seats — those two halves shipped in different releases, and passing only the first is the wave that reports as scoped while its workers are not. Needs both server-side halves; upgrade if you see either refusal.

What a child can reach, and what it cannot

--strict-mcp-config bounds the child's tool surface (GRPH-802). It bounds nothing else: the child runs headless with --dangerously-skip-permissions and a full shell, and whatever CLIs are on the operator's PATH are authenticated to whatever the operator last logged into.

So the supervisor prepends a directory of refusing stubs to each child's PATH (GRPH-818): railway, vercel, fly, heroku, aws, gcloud, az, doctl, kubectl, helm, terraform, op, gh, psql, mysql, mongosh, redis-cli. Each prints why it refused and exits 126.

gbfleet until … --allow psql          # keep local-container verification
gbfleet until … --deny ssh            # add your own

docker is deliberately not denied — children verifying migrations against throwaway Postgres containers is the evidence worth having. gh is denied because the supervisor opens PRs itself now, while gh api is an arbitrary authenticated write to the whole forge.

This stops an agent that wandered, not one that is trying. An absolute path walks straight past it, and a model that wanted to would find that in one step. The honest claim is that a child reaching for a deployment CLI by name gets a refusal, and you read it in a log instead of an incident. A sandbox is what bounds a determined process; this is not one.

And the other half, which no flag fixes: an item's prose is an instruction channel. Nothing checks that a description matches the touchpoints it declares, so anyone who can file a ledger item can write instructions for a process with a shell. Scope waves to PRDs you control.

Seeing a wave before you run it

gbfleet until --repo . --server <url> --project <id> --adapter <vendor> --prd <id> --dry-run

Prints what would be delegated — the free clusters, the held ones with who holds them and when they free, and whether --max-workers is capping the list — then exits. It takes no lock, mints no seat and cuts no worktree, so it can be asked while a wave is already running.

It calls the same collision_clusters the loop calls and applies the same split, rather than modelling the wave separately: a dry run that models it can reassure you about a plan the loop does not have.

When a wave ends because of the vendor, not the fleet

A child that exits before registering reads as a broken adapter, and that is right for almost every case. It was wrong for one whole class. A measured wave ended {"ok": false, "reason": "cap", "spawned": 6, "minted": 0} after three children died in under a second each, reported as adapter 'claude': child exited 1 before registering. stderr tail: — followed by nothing, because stderr was empty. The cause was 67 bytes in stdout.log:

You've hit your session limit · resets 12:20pm (America/New_York)

So the wave blamed the adapter, sent the operator to the vendor CLI, and ended on cap, which means you hit your own --max-children and invites raising it.

until now ends with reason: "vendor_limit" and quotes what the vendor said, including the reset time, and stops rather than spending the rest of its children on a wall it has already hit (GRPH-829). Both streams are read, and both are printed when it really is a crash — a tail of the wrong stream is indistinguishable from a child that said nothing at all. Only claude carries a measured string today; the base adapter matches nothing on purpose, because a matcher that fired on the word "limit" would relabel real crashes as billing problems.

Work recovered from a killed wave

A wave opens by adopting what the last one stranded, and a tree with real work in it is committed as WIP: salvaged by gbfleet. That commit used to stay local: one measured takeover recovered 614 insertions across exactly one item's touchpoints, and the item was re-delegated minutes later, branched from main, and rebuilt every line. The work was recovered and lost in the same move.

Salvaged work now gets the same two steps a finished child's work gets — pushed, then a draft PR naming the item it belongs to, with the receipt written on the item (GRPH-830). The item id comes from the dead child's own record, so a record written by an older supervisor still publishes the branch and simply has nobody to hand the receipt to. A tree whose only uncommitted file was the seat is still not published: ONLY_CREDENTIAL is not SALVAGED, and a pushed empty branch per dead child would make every crash look like work.

Work whose dependency has not landed

done in the ledger means attested, not merged. An attestation binds to a commit and nothing claims that commit went anywhere — so an item can be finished while its work exists only on a feature branch. Children branch from the remote default, so a dependent item would be built without it, and blocked_by cannot warn you: it lists unfinished dependencies, and this one is finished.

until therefore holds an item whose finished dependency's commit is provably not an ancestor of the base, names the dependency and the commit, and moves to the next cluster (GRPH-798). The wave continues on work that is buildable; the remedy is a merge.

A dependency whose commit this clone has never seen is reported and not acted on — that is an unknown, not an absence, and refusing on it would stop every wave on a fresh clone. The base is fetched once per wave first, or a stale remote-tracking ref would measure everything as already merged.

This is a supervisor check and cannot be a server one: the server holds an item id and a commit and has no repository to resolve them against. A human calling delegate by hand is not protected by it.

Or hand the local surface to a planner over stdio:

GBFLEET_API_KEY=... gbfleet mcp --server https://cloud.agentldgr.dev

spawn starts one child and takes no count. The planner decides how many to run — it holds both servers, so it can read collision_clusters and get_backlog itself, mint that many seats, and call spawn once each. The supervisor executes.

Delegate to a seat (PRD-36). A parent that wants one item built on a cheaper model does it in two calls and keeps working: delegate(id, lane, tier, seat=true) on the Graphban server mints a worker seat bound to the item and returns its code; then spawn(enrolment_code=<code>, tier="cheap", item=<id>) here. Registering on a bound seat claims the item server-side, so the child holds it from its first call and never touches claim_cluster; the spawn reply echoes the roster's assigned block (claimed, or taken with who holds it). tier resolves through a table the operator names at launch — gbfleet mcp --tier cheap=gbagent:qwen3.6:35b-a3b-coding-mtp-det --tier frontier=claude:opus — fixed for the life of the process, and an explicit adapter overrides it. gbfleet until takes the same --tier table plus --request cheap|frontier for what its own delegations ask, and mints bound seats for the seeds it delegates, so the divvy no longer decides what its children claim. The outcome comes back through the ledger — the item moving on the board — never as a reply in the parent's context.

The preference matrix (PRD-37). A tier with no --tier flag resolves through src/gbfleet/matrix.toml, a committed table of harness × model × lane × tier rows with a status (verified, unverified, failed, unregistered) and the item that proved it — facts only, reviewed like code. Resolution runs in a fixed order: the rows for the tier → the project's policy (local_only, allowed_harnesses) → the user's profile (an ordered allowlist of harnesses, weights over cost/quality/latency/locality, excludes) → failed rows out → what this machine has installed → score → ties (verified first, then the user's own order, then the row's order). Profile and policy come from the server: gbfleet mcp and gbfleet until read them off fleet_status once at launch (a change is read at the next launch, PRD-36 D16) — the profile is the API key owner's, with a per-project override, edited in the Fleet view under the Wave tab; the policy is the project's. A key whose owner has no profile, or a server that cannot be reached at launch, resolves on matrix order and policy alone and the explanation says profile: none. Cross-vendor review is the server's preference at claim_review, not a matrix rule: reviewer_cross_vendor left with the role axis (PRD-39 S5). Every spawned child is told, in the same sentence as its enrolment code, to register with capabilities={vendor, model?, tier} for what the supervisor actually launched (GRPH-732), so the ledger can attribute its outcome; only a NAMED model is declared, since a vendor default is unknowable from here. Measured quality and latency also ride on fleet_status (per declared vendor × model × lane × tier, with n); the resolver reads the cell for the lane being resolved, never a pooled one, and counts an axis only past n ≥ 5. The spawn reply carries resolution: source (flag or matrix), how many rows survived each step, what each step dropped and why, the winner with its per-axis numbers, and the runner-up. An empty resolution is a tool error naming the step that emptied it — there is no silent default. Measured axes need n ≥ 5 before they count and say unmeasured until then. --matrix PATH on mcp, until and doctor swaps the file; gbfleet doctor prints every row against this machine and what each role/tier would resolve to. The file is TOML, not the YAML the PRD first wrote, because gbfleet is httpx-thin by requirement and tomllib is standard library.

Name the project. A credential that spans several projects resolves a call that names none to its default project, and that is not where the seats were minted: the child registers on the seat's project (the server takes it from the seat), but the supervisor's roster read and the child's own reads land elsewhere — the child never appears on the roster the supervisor polls and reads a backlog that is not its own. gbfleet mcp, gbfleet until and gbfleet doctor take --project <id>, named on every call; doctor fails a multi-project key that gives none. The child learns its project from the registration reply and names it afterwards (GRPH-718, GRPH-719).

What a wave reports about itself. Beyond spawn and reap, up and until print three findings the signing agent otherwise has no way to see, all measured from the worktrees the supervisor already owns and none of them acted on:

• COLLIDED <path>: changed on <branch>, <branch> — two workers changed the same file. The failure the partition exists to prevent, observed rather than predicted: exact paths, no coverage rule, and true whether the touchpoints were wrong or the divvy was.
• UNDECLARED <branch>: changed N file(s) no touchpoint covers — the partition's INPUT was wrong. Compared against the declaration as it stood when work was handed out, which is the snapshot the divvy used. An item that declared nothing is not drift; its areas were predicted, which the board already marks.
• BEHIND <branch>: cut from a base N commit(s) behind origin/main — how much landed on the trunk while the child worked. Two agents can each be green on their own base and conflict on merge, and nothing else in the system can see it: the server has no git, the signing agent gets a branch with no indication of what its diff is against, and the child was cut from HEAD at spawn and never looked again. The trunk is fetched once per wave before measuring — a remote-tracking ref is only as fresh as its last fetch, and a check that skipped it would report every branch as current. BEHIND unmeasured: <reason> when it could not be asked, because that is not the same as nothing having moved.

Vendors and what each of them needs: docs/fleet-adapters.md.

Development

cd fleet
uv venv --python 3.12 .venv
uv pip install -e ".[dev]"
.venv/bin/python -m pytest -q

The suite fails loudly if the package is not installed, rather than testing an uninstalled fallback and passing.