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Gates

docs/workflows/gates.md

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Some workflow steps can't proceed on code alone: a release needs CI to go green, a deploy needs a human sign-off, a cleanup should wait 24 hours. A gate is an issue that represents that wait. It blocks a step the same way any blocker does — the step leaves the ready frontier until the gate closes — so agents never need to poll or spin.

How a gate works

A gate is a bead like any other: created open, it blocks its waiters through a normal dependency edge, and the step becomes ready the moment the gate closes. Gates close in one of two ways:

  • Manuallybd gate resolve <gate-id> (human gates always close this way).
  • Via bd gate check — evaluates open timer and GitHub gates against the real world and closes the ones whose condition is met.
bash
bd gate list                 # open gates
bd gate list --all           # include closed
bd gate show <gate-id>       # details and waiters
bd gate check                # evaluate open gates, close satisfied ones
bd gate check --dry-run      # report without closing
bd gate resolve <gate-id>    # close a gate manually

Gate types

TypeWaits forClosed by
humana person's decisionbd gate resolve only
timera duration after gate creationbd gate check once the timeout elapses
gh:runa GitHub Actions workflow to complete successfullybd gate check (uses gh run view)
gh:pra pull request to mergebd gate check (uses gh pr view)
beada bead in another rig to closecannot be checked because multi-rig routing was removed; resolve these gates manually

Timeouts use Go duration syntax: 30m, 1h, 24h (there is no d unit — write 24h, not 1d).

GitHub gates use the current Git repository by default. To evaluate a PR or workflow run in another repository, set the gate's string metadata.repo value to OWNER/REPO or HOST/OWNER/REPO. An ad-hoc gh:run/gh:pr gate created with bd gate create inherits a valid metadata.repo value from the issue it blocks; human/timer/bead gates do not, since metadata.repo is unrelated, ordinary metadata for those types. bd gate check rejects malformed repository values instead of falling back to the current repository.

Gates in formulas

A formula step declares a gate with a [steps.gate] block. When the formula is instantiated, bd creates the gate issue and wires it as a blocker of that step. The schema has five fields: type, id, await_id, timeout, and repo.

This is the release gate from beads' own release formula — the step that waits for the GitHub release workflow:

toml
[[steps]]
id = "wait-for-ci"
title = "Wait for release workflow"

[steps.gate]
type = "gh:run"
id = "release.yml"       # which workflow to watch
timeout = "30m"          # escalate if it takes longer

For a gh:run or gh:pr gate that watches another repository, set repo the same way a metadata.repo value works for an ad-hoc gate — OWNER/REPO or HOST/OWNER/REPO. Malformed values are rejected when the gate is checked:

toml
[[steps]]
id = "wait-for-downstream"
title = "Wait for downstream release"

[steps.gate]
type = "gh:run"
id = "release.yml"
repo = "org/downstream-repo"   # check gh:run against this repo, not the current one

repo accepts a {{var}} placeholder (e.g. repo = "{{gate_repo}}"); for a formula persisted with bd cook --persist, the placeholder is substituted when the proto is later poured with bd mol pour --var gate_repo=..., the same as title, description, and await_id.

bd gate discover (auto-discovery of a gh:run gate's run ID) requires a workflow name hint (await_id/id, not left blank) for a gate targeting another repository — without one, the local commit/branch heuristics that narrow a same-repo match don't apply across repos, so nothing but the workflow name can identify the right run. A cross-repo gate discovery also ignores the local checkout's branch unless --branch is passed explicitly; an auto-detected local branch has no relationship to the target repo's branches.

A human sign-off gate:

toml
[[steps]]
id = "approve-deploy"
title = "Human approves the deploy"

[steps.gate]
type = "human"

And a cooling-off timer:

toml
[[steps]]
id = "wait-24h"
title = "Let the release bake"

[steps.gate]
type = "timer"
timeout = "24h"

Verify what the parser actually understood before pouring — unknown keys in TOML are dropped silently:

bash
bd formula show <formula> --json   # inspect the parsed gate blocks

Creating gates outside formulas

bd gate create attaches a gate to existing work:

bash
# Block bd-abc until a PR merges
bd gate create --type=gh:pr --blocks bd-abc --await-id=42

# Block bd-abc until a human resolves the gate
bd gate create --type=human --blocks bd-abc --reason "Design sign-off"

# Add another waiter to an existing gate
bd gate add-waiter <gate-id> <issue-id>

Fan-in: waiting on other steps

Waiting on other steps is not a gate — it's a dependency. Use needs to fan in on named steps, and waits_for when a step must wait for dynamically-created children:

toml
[[steps]]
id = "merge-results"
title = "Merge results"
needs = ["test-a", "test-b"]     # fan-in on named steps

[[steps]]
id = "summarize"
title = "Summarize all spawned work"
waits_for = "all-children"       # or "any-children", or "children-of(step-id)"

Working with gated molecules

bash
bd ready --gated        # molecules where a gate just closed (ready to resume)
bd blocked              # what's waiting, and on which gates

Automation patterns: run bd gate check on a schedule (cron, CI, or an orchestrator loop) so timer and GitHub gates close without a human in the loop; keep human gates for the decisions that should never auto-close.