Proposed specificationSource-located exemplarH1

Coordinator-worker spawn flow

Delegate bounded subtasks.

JOIN POINTdelegated_task_spawnRECORD STATUSCandidate · v0.1.0

UML class view

The proposed contract drawn as participant roles, received calls, and numbered dependencies.

Object interactions

The same roles and calls as a class collaboration and a numbered message sequence.

Object interaction diagram for Coordinator-worker spawn flow, showing role collaboration and a numbered message sequence — FIG. P12 / OBJECT INTERACTIONS
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Pointcut

Where the mechanism applies. All four dimensions belong to the proposed match, not just its vocabulary.

Context: A coordinator delegates a bounded task to another execution unit.
Trigger: A worker is spawned, called as a tool, or handed a task.
Structure: Task envelope with identity, instructions, authority, budget, and result target.
Effect: Worker output returns to the coordinator with explicit lifecycle and provenance.

Protected contract

The obligation that clients, operators, and auditors should be able to rely on.

Requires: Parent and child identities, task scope, and shared data policy are known.
Ensures: Each worker has one task record, bounded authority, and a correlated result.
Invariant: Delegation never silently expands permissions or budget.
Violation: Cancellation, worker failure, timeout, and duplicate spawn are typed outcomes.

Negative control

Sequential calls to independent agents without delegation do not count.

Variation & lifecycle

The hot spot is admitted only where the protected semantics survive.

Permitted variation

Sub-agent, agent-as-tool, background agent, child session, and worker pool.

Test obligation

Test authority, timeout, cancellation, duplicate results, and context isolation.

Evolution question

Did delegation gain nested history, approvals, and background lifecycle?

Prompt + code design

An illustrative prompt and a small design sketch for the proposed contract. Names and APIs are invented; this is not a repository excerpt.

PROMPT SKETCH

Spawn workers with one task record each, bounded authority, and a parent correlation id. The parent must receive a result or a failure for every worker it accepted.

CODE DESIGN / PYTHON

def spawn(parent, task, authority):
    worker = parent.runtime.spawn(
        task=task,
        parent_id=parent.id,
        authority=authority.intersect(parent.authority),
        budget=task.budget,
    )
    parent.register(worker.id, task.id)
    return worker

Illustrative design sketch. A child without a task record is an orphan; a parent without a result is incomplete. This example is a teaching aid, not implementation evidence or a conformance claim.

Detection & matching

The frozen rule that retrieves this record, the canonical source exemplar, and the control that should stay unmatched.

Join point: delegated_task_spawn
Source locator: Barbaste et al., §6.4, p. 16 (“Coordinator-Worker Pattern”); Table 11 “Recursive Composition”, p. 52; adapted label
Lexical cue: (?i)\b(?:spawn(?:ed|ing)?|sub[_-]?agent|worker[_-]?agent|delegate(?:d|s|ion)?)\bFrozen expression, v0.1.0. A match is a retrieval cue, not a confirmed implementation.
Aliases: None
Canonical exemplar: OpenHands/software-agent-sdkopenhands-sdk/openhands/sdk/subagent/schema.py:202Support: tests/sdk/subagent/test_subagent_registry.py:1
Negative control: Sequential calls to independent agents without delegation do not count.

Scope-anchored review. pohe-agent analyze <repo> --pattern P12 anchors the cue to its enclosing declaration and checks a separate operational signature for all four pointcut dimensions. Missing roles and negative-control risks remain visible; a structural match is not E2/E3. Calibration report ↗

Repository files

Up to five public files retrieved by the frozen cue and pinned to the audited commit. A match is a place to inspect, not a confirmed implementation.

01OpenHands/software-agent-sdkopenhands-sdk/openhands/sdk/subagent/schema.py:202CANONICAL SOURCE 02aaif-goose/goosecrates/goose/src/acp/handoff.rs:1RETRIEVAL CUE 03affaan-m/ECCskills/council-multi-model/scripts/review-with-codex.js:116RETRIEVAL CUE 04agno-agi/agnolibs/agno/agno/context/fs/provider.py:86RETRIEVAL CUE 05Aider-AI/aideraider/run_cmd.py:13RETRIEVAL CUE

Evidence & provenance

Each layer answers a different question. Do not substitute retrieval for review.

Source-located exemplar

A concrete source anchor is available for this proposed record. It is one exemplar, not evidence that all repositories—or every contract field—conform.

Review boundary: this candidate and its specification come from an AI-assisted study. Independent human validation remains open.

ANY-EVIDENCE FAMILY COVERAGE36/36

100.0% of repository families in the frozen panel have at least one current cue, historical cue, or canonical source layer. This is not confirmed prevalence.

Current lexical-cue repositories: 40 / 41

Canonical source anchorOpenHands/software-agent-sdk 5c524ad65d81openhands-sdk/openhands/sdk/subagent/schema.py:202

Supporting surfacetests/sdk/subagent/test_subagent_registry.py:1

Subagent task and permission envelope.

Exploratory retrieval cue Regex / v0.1.0

This expression is a discovery instrument only. A match is a retrieval cue—not a confirmed implementation, pointcut match, or contract proof.