Proposed specificationSource-located exemplarH1

Parallelization

Run independent work or alternative judgments concurrently.

JOIN POINTfan_out_fan_inRECORD 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 Parallelization, showing role collaboration and a numbered message sequence — FIG. W03 / OBJECT INTERACTIONS
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Pointcut

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

Context: Independent tasks or alternative judgments can run concurrently.
Trigger: A coordinator fans work out and later aggregates it.
Structure: Partition contract, worker identity, result correlation, and reducer.
Effect: All selected results are reconciled into a declared aggregate or failure.

Protected contract

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

Requires: Work partitions are independent enough for concurrency.
Ensures: Aggregation includes every expected result or records its absence.
Invariant: Partial completion is never represented as full agreement.
Violation: Failures, timeouts, and cancellation follow declared quorum or terminal policy.

Negative control

Bare Promise.all without a fan-in contract is only a cue.

Variation & lifecycle

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

Permitted variation

Sectioning, voting, map-reduce, and parallel tool calls.

Test obligation

Test disagreement, correlated failure, timeout, and one missing worker.

Evolution question

Did parallelism add explicit reducers and quorum semantics?

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

Partition only work that is independent enough to run concurrently. Fan in every expected result, record missing partitions explicitly, and do not aggregate a partial set as complete.

CODE DESIGN / PYTHON

def fan_out(partitions, worker):
    futures = [worker.submit(part) for part in partitions]
    results = {}
    for partition, future in zip(partitions, futures):
        try:
            results[partition.id] = future.result()
        except WorkerError as error:
            results[partition.id] = FailedPartition(partition.id, error)
    return Aggregation(results, expected=len(partitions))

Illustrative design sketch. The aggregation contract includes absence; a shorter list is not a successful fan-in. 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: fan_out_fan_in
Source locator: Anthropic
Lexical cue: (?i)\b(?:fan[_-]?out|fan[_-]?in|parallel[_-]?(?:run|agent|workflow)|Promise\.all|asyncio\.gather)\bFrozen expression, v0.1.0. A match is a retrieval cue, not a confirmed implementation.
Aliases: None
Canonical exemplar: openai/openai-agents-pythonexamples/agent_patterns/parallelization.py:7Support: examples/agent_patterns/README.md:45
Negative control: Bare Promise.all without a fan-in contract is only a cue.

Scope-anchored review. pohe-agent analyze <repo> --pattern W03 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.

01openai/openai-agents-pythonexamples/agent_patterns/parallelization.py:7CANONICAL SOURCE 02aaif-goose/goosecrates/goose-cli/src/commands/review/orchestrator.rs:302RETRIEVAL CUE 03agno-agi/agnolibs/agno/agno/knowledge/page/types.py:16RETRIEVAL CUE 04anomalyco/opencodepackages/core/src/git.ts:1287RETRIEVAL CUE 05bytedance/deer-flowbackend/app/channels/manager.py:1680RETRIEVAL 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 COVERAGE24/36

66.7% 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: 28 / 41

Canonical source anchoropenai/openai-agents-python 86bd29878b30examples/agent_patterns/parallelization.py:7

Supporting surfaceexamples/agent_patterns/README.md:45

Parallel alternatives with selection.

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.