Agent Context Partitioner

---
name: agent-context-partitioner
description: >-
  Designs and audits deterministic, authority-filtered partitions of trust-typed context for already admitted bodies or abstract continuation slots. Use when causal context, obligations, disclosure boundaries, vector-space identity, capacity, and omission proofs must survive partitioning. NOT for spawning or admitting agents, choosing worker count, retrieving arbitrary knowledge, writing successor prompts, or granting tools, leases, identity, or effect authority.
license: Apache-2.0
allowed-tools: Read,Grep,Glob
metadata:
  version: "2.0.0"
  category: Agent & Orchestration
  tags: [context, partitioning, authority, causality, continuation, vector-space]
  io-contract:
    kind: structured
    produces:
      - kind: context-partition-proposal-v2
        format: json
        schema: schemas/context-partition-proposal-v2.schema.json
---

# Agent Context Partitioner

Partition only after authority, disclosure, causality, capability, and capacity are explicit. A deterministic assignment heuristic chooses among compatible targets; it cannot repair an infeasible input or create a new body.

## Activate when

- a sealed Context IR must be assigned across admitted bodies;
- a continuation package needs abstract destination requirements without launching a successor;
- open obligations and unresolved effects must be proven present;
- vector-based cohesion must respect immutable embedding-space identity;
- omissions, transfers, and capacity use need a machine-checkable proof.

## Do not activate for

- “spawn more agents,” worker-count selection, or capacity admission;
- identity continuity, process resurrection, or credential transfer;
- general RAG, clustering, prompt writing, or memory retrieval;
- lifecycle fencing, effect reconciliation, capability minting, or lease creation;
- estimating provider quota or subscription usage.

## Modes

- `ACTIVE_SET_PARTITION` targets exact admitted bodies supplied by another authority.
- `CONTINUATION_REQUIREMENTS` targets abstract slots carrying required capabilities and capacity only. A slot has no process, provider session, credential, lease, or identity.

Outputs are `FEASIBLE`, `INFEASIBLE`, or `UNKNOWN`. Never emit `READY`, `AUTHORIZED`, `ADMITTED`, or `SPAWN`.

## Hard order of operations

```mermaid
flowchart TD
  A[Sealed trust-typed Context IR] --> B[Verify source root and policy]
  B --> C[Filter targets by tenant, disclosure, audience, and current guidance]
  C --> D[Close causal parents, obligations, unresolved effects, and capabilities]
  D --> E[Check singleton and aggregate capacity]
  E -->|Any hard gap| F[INFEASIBLE or UNKNOWN with exact gap]
  E -->|Feasible set| G[Apply deterministic greedy assignment rule]
  G --> H[Emit assignments, typed transfers, omissions, and coverage proof]
  H --> I[Validate proposal against original root]
  I --> J[PrepareContinuation input only]
  J -. separate lifecycle authority .-> K[AdmitSuccessor]
```

1. **Bind the root.** Record source snapshot, content digest, policy digest, and complete item inventory.
2. **Separate guidance from evidence.** Only current, audience-matching, revocation-checked guidance may enter a directive channel. Facts and history remain cited data.
3. **Filter before scoring.** Tenant, harbor, repository, disclosure, retention, and capability rules define the feasible set.
4. **Close dependencies.** Every causal parent, open obligation, unresolved effect, and non-droppable item is assigned, transferred through an authorized edge, or blocks the plan.
5. **Respect capacity.** Oversized singleton items and aggregate target overflow are hard failures.
6. **Choose a deterministic candidate.** The included `partition_feasibility.py` orders items topologically, then prefers a compatible target already holding parents, lower projected token use, and lexical target ID. This is a greedy heuristic, not an optimal graph partitioner. Do not use semantic similarity in the current algorithm.
7. **Prove coverage.** Every input item receives one inventory disposition: `ASSIGNED`, `TRANSFERRED`, `OMITTED_ALLOWED`, or `BLOCKED`.

## Context IR invariants

- Only `CURRENT_GUIDANCE` with current envelope, audience, scope, verification, and revocation evidence may be directive.
- Primary evidence, cited derivations, historical intent, and untrusted content remain data.
- Open obligations, unresolved effects, lineage, and causal parents are non-droppable.
- Summaries and compactions cannot become primary roots.
- Missing authority, provenance, or revocation evidence yields `UNKNOWN`, never a permissive guess.
- A tombstone may replace deleted content, but derived vectors and projections must identify the invalidated source revision.

## Retrieval-space identity

A vector-bearing item binds model artifact/config, preprocessing, chunker, pooling, dimensions, normalization, metric, coordinate precision, quantization, redaction policy, modality, and derived `spaceId`. Provider name and transport are provenance, not compatibility.

- Compare vectors only when `spaceId` is identical.
- Equal dimensions are insufficient.
- Mismatch disables the semantic objective; it does not authorize full-copy fallback.
- Re-embedding creates a new item revision and separately receipted migration.

See [`references/retrieval-space-identity.md`](references/retrieval-space-identity.md) for the exact digest recipe.

## Coverage and omission

Allowed omissions are limited to `OUT_OF_SCOPE`, `RETENTION_REDACTED_WITH_TOMBSTONE`, `EXPIRED_DISPOSABLE`, `DUPLICATE_CONTENT_HASH`, and `SUPERSEDED_PROJECTION`. `DESTINATION_INCOMPATIBLE`, `UNKNOWN_SOURCE`, and `SIZE_EXCEEDED` are blocking gaps.

Coverage proves completeness only relative to the supplied root and obligation set. It cannot prove the root discovered every relevant fact.

## Prepare is not admit

The proposal may feed `PrepareContinuation`. It does not fence a predecessor, reconcile an effect, reserve capacity, mint a capability, select a process, consume a nonce, or create lineage. A lifecycle authority may later run `AdmitSuccessor` only after independent fence, effect, capacity, guidance, and context receipts.

## Anti-patterns

### Optimize, then filter

**Wrong:** cluster first and remove forbidden assignments later.

**Right:** authority and disclosure define the feasible graph before any score exists.

### Same dimensions, same space

**Wrong:** compare two 768-dimensional vectors.

**Right:** require identical immutable `spaceId`.

### K proposal means birth

**Wrong:** turn a capacity gap into “spawn another worker.”

**Right:** emit the exact missing capability or capacity with no lifecycle action.

### Summary becomes source

**Wrong:** repartition yesterday's summary.

**Right:** regenerate from primary roots and use summaries only to test omissions.

## Output and validation

- [`schemas/context-partition-proposal-v2.schema.json`](schemas/context-partition-proposal-v2.schema.json) — proposal contract.
- [`examples/valid-proposal.json`](examples/valid-proposal.json) — example schema-valid proposal.
- [`scripts/validate-context-partition.mjs`](scripts/validate-context-partition.mjs) — proposal validator and digest checks.
- [`scripts/test-bundle.mjs`](scripts/test-bundle.mjs) — positive and adversarial schema/domain mutations.
- [`algorithms/partition_feasibility.py`](algorithms/partition_feasibility.py) — deterministic assignment against supplied items and targets, no spawning or effects.
- [`algorithms/test_partition_feasibility.py`](algorithms/test_partition_feasibility.py) — local fixtures for missing evidence, capacity, cycles, and explicit cross-target transfers.
- [`references/context-ir-and-continuation.md`](references/context-ir-and-continuation.md) — field semantics and lifecycle boundary.
- [`references/partition-procedure.md`](references/partition-procedure.md) — algorithm steps, constraints, and a worked example.
- [`references/retrieval-space-identity.md`](references/retrieval-space-identity.md) — exact vector-space compatibility.
- [`tests/activation.md`](tests/activation.md) — activation corpus.

```bash
node skills/agent-context-partitioner/scripts/validate-context-partition.mjs \
  skills/agent-context-partitioner/examples/valid-proposal.json
node skills/agent-context-partitioner/scripts/test-bundle.mjs
```

Static validity is not optimality, complete discovery, safe execution, or successor admission.


## Contract boundary at a glance

```mermaid
flowchart LR
  A[Supplied Context IR and target inventory] --> B[Partition proposal and coverage proof]
  B --> C[Validator checks schema, digest, and joins]
  C --> D[FEASIBLE relative to this supplied input]
  C --> E[INFEASIBLE or UNKNOWN with gaps]
  D --> F[PrepareContinuation input only]
  F -. separate lifecycle authority .-> G[Admission decision]
  G --> H[Possible runtime creation outside this skill]
```

A green result proves neither complete discovery nor that the supplied inventory is authoritative. It also does not imply an agent, process, tool capability, prompt, or effect was created.