Cue Configuration

Cue is configured via a .maestro/cue.yaml file placed inside the .maestro/ directory at your project root. The engine watches this file for changes and hot-reloads automatically.

File Location

your-project/
├── .maestro/
│   └── cue.yaml        # Cue configuration
├── src/
├── package.json
└── ...

Maestro discovers this file automatically when the Cue Encore Feature is enabled. Each agent that has a .maestro/cue.yaml in its project root gets its own independent Cue engine instance.

One cue.yaml per agent project root. The engine reads ONLY <projectRoot>/.maestro/cue.yaml for each agent - it does not walk parent directories and does not fall back to any ancestor or workspace-wide config. If your fleet has agents at multiple project roots, you maintain one cue.yaml per root. See Multi-root pipelines below.

Full Schema

# Pipeline comment - groups subscriptions into a named pipeline in the UI
# Pipeline: My Pipeline (color: #06b6d4)

# Subscriptions define trigger-prompt pairings
subscriptions:
  - name: string # Required. Unique identifier for this subscription
    event: string # Required. Event type (see Event Types)
    enabled: boolean # Optional. Default: true
    prompt: string # Required (or use prompt_file). Inline prompt text
    prompt_file: string # Required (or use prompt). Path to a .md file
    output_prompt: string # Optional. Follow-up prompt sent after the main run completes
    output_prompt_file: string # Optional. Path to a .md file for the output prompt
    label: string # Optional. Human-readable label displayed in the Cue dashboard
    agent_id: string # Optional. UUID of the target agent

    # Event-specific fields
    interval_minutes: number # Required for time.heartbeat
    schedule_times: list # Required for time.scheduled (HH:MM strings)
    schedule_days: list # Optional for time.scheduled (mon, tue, wed, thu, fri, sat, sun)
    watch: string # Required for file.changed, task.pending (glob pattern)
    source_session: string | list # Required for agent.completed (display name or list of names)
    source_session_ids: string | list # Optional companion to source_session - agent UUID(s). Preferred at runtime; survives renames
    source_sub: string | list # Optional. Upstream subscription name(s) - required when action is "command". Aligns positionally with source_session arrays
    fan_out: list # Optional. Target agent display names for fan-out
    fan_out_ids: list # Optional companion to fan_out - agent UUIDs (parallel array). Preferred at runtime; survives renames
    filter: object # Optional. Payload field conditions
    repo: string # Optional for github.* (auto-detected if omitted)
    poll_minutes: number # Optional for github.*, task.pending

# Global settings (all optional - sensible defaults applied)
settings:
  timeout_minutes: number # Default: 30. Max run duration before timeout
  timeout_on_fail: string # Default: 'break'. What to do on timeout: 'break' or 'continue'
  max_concurrent: number # Default: 1. Simultaneous runs (1-10)
  queue_size: number # Default: 512. Max queued events (0-10000; 0 disables buffering)
  owner_agent_id: string # Optional. Pin this cue.yaml to a single agent (id or name). See "Sharing a workspace".

When two or more agents are registered against the same project directory (for example, one agent using Opus and another using Sonnet, both pointing at the same vault), every unowned subscription (one without an explicit agent_id) would otherwise fire once per agent. Maestro resolves this as follows:

settings.owner_agent_id set and matched by some agent in the root - that agent is the owner; other agents in the same root skip unowned subscriptions.
settings.owner_agent_id set but matched by nobody - the config is dead. Every agent in that project root skips unowned subscriptions, and each row in the Cue dashboard is flagged with a red warning linking to this setting.
settings.owner_agent_id unset and multiple agents share the root - the first agent in the session list wins. Non-winner rows in the Cue dashboard are flagged with a red warning naming the winner and pointing to owner_agent_id as the override.

Accepted values for owner_agent_id: the agent’s internal id (UUID) or its display name (e.g. Obsidian). Subscriptions with an explicit agent_id continue to fan out independently of ownership - useful when a single shared config intentionally targets multiple agents in the same workspace.

Multi-root pipelines (agents in different project roots)

When a pipeline spans agents that live in different project roots, it is physically multiple cue.yaml files - one per participating agent’s project root. The engine never aggregates yaml across roots, so a “single root cue.yaml” is not a reliable pattern for a multi-root agent fleet. The rule: Each subscription lives in the .maestro/cue.yaml of the agent that owns it. “Owning agent” = the agent whose agent_id matches the subscription’s agent_id field. Cross-agent chains between subscriptions in different files are stitched at runtime via the standard source_session / fan_out fields plus their UUID-keyed companions (source_session_ids / fan_out_ids) - no shared file required. Where each role lives:

Subscription role	Lives in cue.yaml under…
Trigger consumed by agent A (e.g. `file.changed` that prompts agent A)	Agent A’s project root
Fan-out from A to [B, C, D]	Agent A’s project root (set `fan_out` + `fan_out_ids`)
`agent.completed` chain step where upstream is X, downstream is Y	Agent Y’s project root (set `source_session` + `source_session_ids` to X)
Fan-in synthesis where upstreams are A, B, C and downstream is Z	Agent Z’s project root (set `source_session` + `source_session_ids` to [A, B, C])
Command node (`action: command`) attached to agent W’s session	Agent W’s project root (it shares W’s session and cwd)

Orchestration “at the root.” If you have an orchestrator agent whose project root sits above the worker agents in the filesystem, the orchestrator’s own .maestro/cue.yaml is naturally where fan-in / synthesis subscriptions land - because it owns those subscriptions, not because it is “the root.” Workers’ triggers still live in each worker’s own cue.yaml. Always set source_session / fan_out; add the _ids companions for rename stability. The validator requires source_session on every agent.completed subscription, and fan_out is the canonical field for fan-out targets. Additionally populate the parallel UUID arrays - source_session_ids: [<agent-uuid>] next to source_session: <agent-name>, fan_out_ids: [<uuid>, ...] next to fan_out: [<name>, ...]. The dispatcher prefers ids at lookup time and falls back to names, so cross-root edges survive an upstream agent rename. Omitting the ids works but silently breaks on rename. Pipeline grouping across files. A pipeline that spans roots still appears as one card in the Cue dashboard / Pipeline Editor as long as every participating subscription carries the same pipeline_name (and same # Pipeline: Name (color: #hex) comment header in each file). The visual editor handles this automatically; if you hand-author, keep the values consistent across every file. The visual editor is the easy path. When you save a multi-root pipeline from the Pipeline Editor, Maestro automatically partitions the subscriptions by owning agent’s project root and writes one yaml per participating cwd. If you find yourself authoring a multi-root pipeline by hand and it gets fiddly, building it in the Pipeline Editor and letting it emit the per-cwd files is the supported path.

Subscriptions

Each subscription is a trigger-prompt pairing. When the trigger fires, Cue sends the prompt to the agent.

Required Fields

Field	Type	Description
`name`	string	Unique identifier. Used in logs, history, and as a reference in chains
`event`	string	One of the nine event types
`prompt`	string	The prompt to send as inline text. Required unless `prompt_file` is specified

Either prompt or prompt_file must be provided. If both are present, prompt_file takes precedence.

Optional Fields

Field	Type	Default	Description
`enabled`	boolean	`true`	Set to `false` to pause a subscription without removing it
`agent_id`	string (UUID)	-	UUID of the target agent. Auto-assigned by the Pipeline Editor
`prompt_file`	string	-	Path to a `.md` file containing the prompt (alternative to inline `prompt`)
`interval_minutes`	number	-	Timer interval. Required for `time.heartbeat`
`schedule_times`	list of strings	-	Times in `HH:MM` format. Required for `time.scheduled`
`schedule_days`	list of strings	-	Days of week (`mon`-`sun`). Optional for `time.scheduled`
`watch`	string (glob)	-	File glob pattern. Required for `file.changed`, `task.pending`
`source_session`	string or list	-	Source agent display name(s). Required for `agent.completed`
`source_session_ids`	string or list	-	Companion UUID(s) for `source_session`. Same shape (string ↔ string, list ↔ list). Preferred by the dispatcher at lookup time; falls back to `source_session` names when absent. Set this alongside `source_session` for rename stability
`source_sub`	string or list	-	Upstream subscription name(s) that narrow chain matching. Required when `action: command` on `agent.completed`. When `source_session` is an array, `source_sub` must be a same-length array (positional pairing)
`fan_out`	list of strings	-	Target agent display names to fan out to
`fan_out_ids`	list of strings	-	Companion UUID array for `fan_out` (one entry per fan-out target). Preferred by the dispatcher at lookup time; falls back to `fan_out` names when absent. Set this alongside `fan_out` for rename stability
`filter`	object	-	Payload conditions (see Filtering)
`repo`	string	-	GitHub repo (`owner/repo`). Auto-detected from git remote
`poll_minutes`	number	varies	Poll interval for `github.*` (default 5) and `task.pending` (default 1)
`output_prompt`	string	-	Follow-up prompt sent after the main run completes successfully
`output_prompt_file`	string	-	Path to a `.md` file for the output prompt (alternative to inline)
`label`	string	-	Human-readable label displayed in the Cue dashboard and pipeline editor

Prompt Field

Prompts can be provided inline or via a separate file. Inline prompt:

prompt: |
  Please lint the file {{CUE_FILE_PATH}} and fix any errors.

File reference (using prompt_file):

prompt_file: .maestro/prompts/my-prompt.md

File paths are resolved relative to the project root. Prompt files support the same {{VARIABLE}} template syntax as inline prompts. Using prompt_file keeps your cue.yaml clean when prompts are long or complex - the Pipeline Editor uses this approach by default, storing prompt files in .maestro/prompts/.

Output Prompt (Two-Phase Runs)

The output_prompt field enables a two-phase execution pattern. When the main prompt completes successfully, Cue automatically sends the output_prompt as a follow-up - with the first run’s output included as context. This is useful for workflows where one phase generates data and a second phase acts on it:

subscriptions:
  - name: test-and-report
    event: time.heartbeat
    interval_minutes: 60
    prompt: |
      Run the full test suite with `npm test` and capture the results.
    output_prompt: |
      Based on the test results above, generate a summary report.
      Include pass/fail counts and highlight any regressions.

You can also use output_prompt_file to reference a .md file instead of inline text:

subscriptions:
  - name: analyze-and-summarize
    event: file.changed
    watch: 'src/**/*.ts'
    prompt: Analyze {{CUE_FILE_PATH}} for code quality issues.
    output_prompt_file: prompts/summarize-analysis.md

The output prompt only fires when the main run completes successfully. If the main run times out or fails, the output phase is skipped.

Pipelines

A pipeline groups multiple subscriptions under a single name in the Pipeline Editor. This is useful when you have related automations (e.g., a daily scan and a weekly review) that logically belong together. Defining a pipeline: Add a pipeline comment at the top of your cue.yaml, then use a naming convention to group subscriptions:

# Pipeline: My Pipeline (color: #06b6d4)

subscriptions:
  - name: My Pipeline
    event: time.scheduled
    schedule_times:
      - '09:00'
    prompt_file: .maestro/prompts/my-pipeline-daily.md

  - name: My Pipeline-chain-1
    event: time.scheduled
    schedule_times:
      - '17:00'
    prompt_file: .maestro/prompts/my-pipeline-eod.md

How it works:

The # Pipeline: Name (color: hex) comment declares the pipeline name and its color in the UI
The first subscription’s name matches the pipeline name exactly
Additional subscriptions in the same pipeline use the convention Name-chain-N (e.g., My Pipeline-chain-1, My Pipeline-chain-2)
All subscriptions with matching names appear as separate trigger lines within a single pipeline in the Pipeline Editor

Notes:

The color in the comment sets the pipeline’s dot color in the UI (any valid hex color)
Each subscription in a pipeline can have its own event type, schedule, and prompt - they don’t need to share configuration
Use the label field to give each line a descriptive name (e.g., “Daily Analysis”, “Weekly Review”)
The Pipeline Editor creates this structure automatically when you use the visual editor

Visual-node identity (target_node_key, fan_out_node_keys): When you save from the Pipeline Editor, you may see UUID-valued target_node_key / fan_out_node_keys fields on subscriptions. These are renderer-only - the Cue engine ignores them. They let the editor distinguish “two visual nodes that happen to point at the same agent” (different keys → two nodes on the canvas) from “one shared node with multiple inputs” (same key → explicit fan-in onto a single node). If you hand-edit YAML and want two separate visual instances of the same agent for the same trigger, give each sub a different target_node_key; if you want them to merge into one fan-in target, give them the same key. Leave the keys alone when round-tripping through the editor - clearing them silently re-merges your visual nodes by agent_id on the next reload.

Agent-authored Trigger -> Command -> Agent YAML checklist

If an AI agent writes cue.yaml directly (without using the visual editor), include all of the following so Maestro reconstructs the graph correctly:

Initial trigger subscription uses action: command with a valid command object.
The downstream agent.completed subscription includes source_sub pointing to that command subscription name.
For fan-in chains, when source_sub / source_session / source_session_ids are arrays, all three must be the same length and positionally aligned: index i in each array refers to the same upstream source. The validator rejects mismatched lengths.
Keep pipeline_name consistent across all subs in the pipeline.
Keep per-node identity fields (target_node_key, fan_out_node_keys) stable once created.

Example:

subscriptions:
  - name: Build Pipeline-cmd-1
    pipeline_name: Build Pipeline
    event: time.scheduled
    schedule_times: ['09:00']
    action: command
    command:
      mode: shell
      shell: npm run build
    agent_id: AGENT_UUID_A
    target_node_key: node-cmd-1

  - name: Build Pipeline-chain-1
    pipeline_name: Build Pipeline
    event: agent.completed
    source_session: Agent A
    source_session_ids: [AGENT_UUID_A]
    source_sub: Build Pipeline-cmd-1
    prompt: "{{CUE_SOURCE_OUTPUT}}\n\nSummarize build output and next steps."
    agent_id: AGENT_UUID_A
    target_node_key: node-agent-1

Labels

The label field provides a human-readable name displayed in the Cue dashboard and pipeline editor. When subscriptions are grouped into a pipeline, the label distinguishes each line within the pipeline.

subscriptions:
  - name: pr-review
    label: 'PR Review Bot'
    event: github.pull_request
    prompt: Review the PR at {{CUE_GH_URL}}.

Disabling Subscriptions

Set enabled: false to pause a subscription without deleting it:

subscriptions:
  - name: nightly-report
    event: time.heartbeat
    interval_minutes: 1440
    enabled: false # Paused - won't fire until re-enabled
    prompt: Generate a daily summary report.

Settings

The optional settings block configures global engine behavior. All fields have sensible defaults - you only need to include settings you want to override.

timeout_minutes

Default: 30 | Type: positive number Maximum duration (in minutes) for a single Cue-triggered run. If an agent takes longer than this, the run is terminated.

settings:
  timeout_minutes: 60 # Allow up to 1 hour per run

timeout_on_fail

Default: 'break' | Type: 'break' or 'continue' What happens when a run times out:

break - Stop the run and mark it as failed. No further processing for this event.
continue - Stop the run but allow downstream subscriptions (in fan-in chains) to proceed with partial data.

settings:
  timeout_on_fail: continue # Don't block the pipeline on slow agents

max_concurrent

Default: 1 | Type: integer, 1-10 Maximum number of Cue-triggered runs that can execute simultaneously for this agent. Additional events are queued.

settings:
  max_concurrent: 3 # Allow up to 3 parallel runs

queue_size

Default: 512 | Type: integer, 0-10000 Maximum number of events that can be queued when all concurrent slots are occupied. Events beyond this limit are dropped. Default is 512 - generous enough to absorb bursty triggers without surfacing overflow toasts. Lower it to backpressure faster; set to 0 to drop any event that can’t run immediately.

settings:
  queue_size: 1024 # Buffer up to 1024 events

Validation

The engine validates your YAML on every load. Common validation errors:

Error	Fix
`"name" is required`	Every subscription needs a unique `name` field
`"event" is required`	Specify one of the nine event types
`"prompt" is required`	Provide inline text or a file path
`"interval_minutes" is required`	`time.heartbeat` events must specify a positive interval
`"schedule_times" is required`	`time.scheduled` events must have at least one `HH:MM` time
`"watch" is required`	`file.changed` and `task.pending` events need a glob pattern
`"source_session" is required`	`agent.completed` events need the name of the source agent
`"max_concurrent" must be between 1-10`	Keep concurrent runs within the allowed range
`"queue_size" must be between 0-10000`	Keep queue size within the allowed range
`filter key must be string/number/bool`	Filter values only accept primitive types

The inline YAML editor in the Cue Modal shows validation errors in real-time as you type. A green Valid YAML indicator at the bottom confirms your config parses correctly.

Complete Example

A realistic configuration demonstrating a pipeline with multiple trigger lines, mixed event types, and external prompt files:

# Pipeline: DevOps (color: #10b981)

subscriptions:
  # Lint TypeScript files on save
  - name: DevOps
    label: Lint on Save
    event: file.changed
    watch: 'src/**/*.ts'
    filter:
      extension: '.ts'
    prompt: |
      The file {{CUE_FILE_PATH}} was modified.
      Run `npx eslint {{CUE_FILE_PATH}} --fix` and report any remaining issues.

  # Morning standup on weekdays
  - name: DevOps-chain-1
    label: Morning Standup
    event: time.scheduled
    schedule_times:
      - '09:00'
    schedule_days:
      - mon
      - tue
      - wed
      - thu
      - fri
    prompt: |
      Generate a standup report from recent git activity.

  # Review new PRs automatically
  - name: DevOps-chain-2
    label: PR Review
    event: github.pull_request
    poll_minutes: 3
    filter:
      draft: false
    prompt: |
      A new PR needs review: {{CUE_GH_TITLE}} (#{{CUE_GH_NUMBER}})
      Author: {{CUE_GH_AUTHOR}}
      Branch: {{CUE_GH_BRANCH}} -> {{CUE_GH_BASE_BRANCH}}
      URL: {{CUE_GH_URL}}

      {{CUE_GH_BODY}}

      Please review this PR for code quality, potential bugs, and style issues.

  # Work on pending tasks from TODO.md
  - name: DevOps-chain-3
    label: Task Worker
    event: task.pending
    watch: 'TODO.md'
    poll_minutes: 5
    prompt: |
      There are {{CUE_TASK_COUNT}} pending tasks in {{CUE_TASK_FILE}}:

      {{CUE_TASK_LIST}}

      Pick the highest priority task and complete it.
      When done, check off the task in the file.

settings:
  timeout_minutes: 45
  max_concurrent: 2
  queue_size: 15

All four subscriptions appear as separate trigger lines within a single DevOps pipeline in the Pipeline Editor.

Documentation Index

​File Location

​Full Schema

​Sharing a workspace across agents

​Multi-root pipelines (agents in different project roots)

​Subscriptions

​Required Fields

​Optional Fields

​Prompt Field

​Output Prompt (Two-Phase Runs)

​Pipelines

​Agent-authored Trigger -> Command -> Agent YAML checklist

​Labels

​Disabling Subscriptions

​Settings

​timeout_minutes

​timeout_on_fail

​max_concurrent

​queue_size

​Validation

​Complete Example

File Location

Full Schema

Sharing a workspace across agents

Multi-root pipelines (agents in different project roots)

Subscriptions

Required Fields

Optional Fields

Prompt Field

Output Prompt (Two-Phase Runs)

Pipelines

Agent-authored Trigger -> Command -> Agent YAML checklist

Labels

Disabling Subscriptions

Settings

timeout_minutes

timeout_on_fail

max_concurrent

queue_size

Validation

Complete Example