Configuration Surface¶

Reasoning behavior is configured at four boundaries: the problem specification, the execution policy, the command invocation, and the process environment. Keep all four with a run when reproducibility matters.

Problem specification¶

The JSON ProblemSpec is the durable input contract. Its constraints object also selects retrieval and evidence behavior:

Constraint	Default	Effect
`needs_retrieval`	`false`	use the local BM25 runtime when a corpus is available
`corpus_path`	packaged small corpus when retrieval is requested and the fixture is available	JSONL corpus used by local retrieval
`chunk_chars`	`800`	target chunk size
`overlap_chars`	`120`	character overlap between adjacent chunks
`bm25_k1`	`1.2`	BM25 term-frequency saturation
`bm25_b`	`0.75`	BM25 length normalization
`min_supports_per_claim`	`2`	minimum evidence references for a derived claim; values are clamped to at least one
`max_citations`	minimum support count	maximum citations selected for a derivation; never lower than the minimum support count

For example:

{
  "description": "Identify the evidence-supported conclusion",
  "constraints": {
    "needs_retrieval": true,
    "corpus_path": "data/corpus.jsonl",
    "chunk_chars": 800,
    "overlap_chars": 120,
    "bm25_k1": 1.2,
    "bm25_b": 0.75,
    "min_supports_per_claim": 2,
    "max_citations": 4
  }
}

Relative corpus paths are resolved from the process working directory. Use a pinned corpus file and record its digest rather than depending on mutable input.

Run and verification controls¶

The CLI run surface accepts the specification path, preset name, integer seed, artifact root, and --fail-on-verify. The content-derived run identifier includes the specification identifier, preset, seed, and runtime fingerprint; changing any of them intentionally creates a different run identity.

The Python executor additionally accepts ExecutionPolicy. Its defaults are fail_fast=True and min_supports_per_claim=2; a specification constraint can override the latter. Verification accepts strict, audit, or permissive policy mode. Replay has its own --fail-on-diff gate.

Environment controls¶

Variable	Default	Meaning
`RAR_RETRIEVAL_CORPUS_MAX_BYTES`	`0`	corpus byte ceiling; zero disables the ceiling
`RAR_RUN_DISK_QUOTA_BYTES`	`0`	run-directory disk ceiling; zero disables it
`RAR_RUN_TIME_BUDGET_SEC`	`0`	elapsed-time budget checked after execution; zero disables it
`RAR_RUN_CPU_BUDGET_SEC`	`0`	CPU-time budget checked after execution; zero disables it
`RAR_API_TOKEN`	unset	exact token required in `x-api-token` when configured
`RAR_API_RATE_LIMIT`	`0`	process-local request limit; zero disables rate limiting

The resource budgets are read when the run-artifact module is imported. Set them before starting the process. Time and CPU budgets are post-run checks, not preemptive cancellation controls.

The HTTP application accepts an artifact root when it is created; otherwise it uses artifacts/bijux-canon-reason. That root owns both run artifacts and the SQLite item store.