# General-purpose evolution migration hiveloom 1.2.0 carries the reusable parts of the ARC-AGI-2 benchmark work into the library. This note records what generalized, what was corrected on the way, and what was deliberately left out. The ARC dataset, scorer, harness assets, experiment outputs, and benchmark-specific research scripts are not part of the package. This historical migration is separate from the packaged [research programs](research.md) added in 1.3.0. ## Included in 1.2.0 | Improvement | Why it generalizes | Release behavior | |---|---|---| | Attempt memory | Any iterative search can repeat a rejected or reverted experiment when feedback is missing. | Recent resolved queue proposals become history; SDK drivers can supply measured histories across versions. | | Operator findings | Passing validators do not reveal every opportunity, and old clusters may no longer describe the bottleneck. | `evolve --note` and `analyze(analyst_notes=...)` support findings even without failed runs. | | Proposal repair | Models can violate output schemas or omit objective expectations on any task. | Up to three calls, with bounded feedback; invalid evidence fails before a call. | | Bounded evidence | Documents, logs, retrieval results, and code can overwhelm a proposing prompt. | Redaction precedes truncation; history, findings, and failure evidence have section limits. | | Model capabilities and provider parameters | Output limits and request controls vary by endpoint, independently of benchmark. | Positive registered output limits, validated `model.max_tokens`, bounded frozen `model.params`, and configurable transport timeouts. | | Truncation recovery | A length-limited reply is not reliable evidence of a completed answer. | Continue within configured budgets; preserve partial output; enforce policy and verification; report `truncated` and indexed friction. | | Provider normalization and retries | Interrupted reads, HTTP-200 error envelopes, blank content, and large reasoning payloads are transport concerns. | Transient failures retry; overflow remains classifiable; useful output survives bounded metadata/reasoning handling. | | Hook signature validation | A callback accepting `**kwargs` cannot consume a second positional argument. | Reject that mismatch during validation instead of discovering it during a run. | The evolution improvements apply to extraction, retrieval, triage, code tasks, and other domains with measurable outcomes. Transport fixes improve execution reliability. Neither category by itself establishes a task-quality gain; that requires evaluation against an appropriate baseline. ## Corrections made during extraction - Redact history, operator findings, and the current spec as well as failure records. Preserve key/path redaction by applying it before separating sections. - Bound caller-supplied histories and wide collections, not only individual diffs. - Preserve rejected paths and rejection reasons. Treat queue decisions as unmeasured, and inconclusive experiments as uncertain rather than refuted. - Remove prompt claims that two failed prompt edits disprove all prompt changes, or that sampling is the only way to address a wrong answer. - Include findings and histories in proposal deduplication, so new evidence cannot silently return an older pending proposal. - Reject inconsistent metric directions before paying for proposal retries. Schema-repair feedback does not echo invalid values into the next prompt. - Preserve the configured executor token budget. A provider's capability is not authorization to double the runtime budget after truncation. - Report exhausted truncation as a failure unless actual verification succeeds; required phases cannot be bypassed. Productive policy turns reset the streak. - Block request aliases and controls that could bypass identity, transcript, tool, output-budget, streaming, or response-count handling. Validate parameters as bounded JSON and forward them through both built-in provider families. - Bound reasoning when it is the visible-text fallback, not just when attached beside a normal answer. Ignore malformed nonscalar routing metadata. - Keep the historical strong-model output default for unknown capabilities; a guessed large request can be rejected by smaller endpoints. ## General-purpose work deferred ### Multiple-attempt consensus (`best_of_n`) `best_of_n` ships in 1.2.0 as an experimental policy. The concept is reusable, especially for tasks with canonical, short answers, but these limitations are open and should be weighed before relying on it: 1. `context_rewound` is emitted by the new context operation but is not handled by journal replay. Forks/materialization can reconstruct a different context. 2. Rewinding messages does not isolate tool side effects, artifacts, or mutable tool state. Independence is not guaranteed for arbitrary harnesses. 3. The saved prefix is a message count; compaction can change the messages at those positions. Store the intended prefix or define a compatible reset. 4. Whitespace normalization can equate distinct string or code outputs. Answer equivalence needs an explicit contract, not a universal whitespace rule. 5. Verification sees accumulated run evidence, while the selected answer may come from a different attempt. Define evidence ownership, retries, and budget-exhaustion behavior before claiming the chosen answer is verified. Follow-up work: a consensus-policy release pass. ### Evaluation-driven keep/revert decisions *Landed in 1.2.0 as `hiveloom assess` and `evolve --experiment`* — see [signal-driven-evolution.md](signal-driven-evolution.md). The contract below is what shaped it: McNemar only for paired binary outcomes and the sign test for paired metrics; a target stated before measuring; the success rate as a guard that no target win overrides; inconclusive kept distinct from refuted and reverted by default; the incumbent re-measurable each round. Confirmation on held-out evidence remains the operator's job. The ARC scripts contain reusable ideas: paired per-case comparisons, repeated measurements, re-measuring the incumbent, recording inconclusive results, tracking diagnostic metrics, and avoiding task selection based on unusually low baseline scores. These belong near generic eval comparison/experiment APIs. Do not move `scripts/decide.py` into the library unchanged. Its sign counts support a directional sign test for general numeric scores; calling it McNemar is specific to binary paired outcomes. It also permits a diagnostic-metric win to keep a candidate when primary quality is inconclusive. Failure to detect a regression is not proof that quality was preserved. A general decision contract needs explicit metric directions and constraints, case/repetition coverage, effect-size requirements, missing-data handling, and an approach to repeated searches and multiple metric comparisons. Confirm selected candidates on fresh or held-out evidence before making release-quality claims. ### Opt-in adaptive output budgets Automatic budget growth may be useful, but should have an operator-owned, frozen ceiling and explicit accounting/replay semantics. It is deliberately excluded from this release; users can raise `model.max_tokens` through the CLI. ## ARC-specific work kept out of the package `evals/arc-agi-2/`, its grid parser, official attempt scoring, dataset fetching, training-pair hypothesis tools, validators, protocol arms, and benchmark test module stay with the benchmark work, outside the library. The experiment scripts keep their benchmark-specific metric names; the generic contract they motivated ships as `hiveloom assess` and `evolve --experiment`. ## Compatibility and release notes - No `harness.yaml` was hand-edited. Frozen evolution paths and approval gates remain enforced. - Empty `model.params` is omitted from canonical serialization, preserving existing harness hashes and evidence cohorts. - New `model.params` and capability fields are additive. Configurations with invalid capabilities or reserved request fields now fail validation. - Callers should recognize the new `truncated` run status; CLI exit code is 4. - Known strong-model capabilities can increase generation/evolution output allowances, and proposal repair can make up to three model calls. Executor output budgets remain unchanged. - Attempt memory covers every applied evolution — queued or applied directly with `evolve --yes` — each with its measured verdict from `hiveloom assess` or the keep/revert decision of `evolve --experiment`, plus rejected proposals. SDK drivers may still pass their own ledger. History is advice to the proposer, not a guarantee against duplicates or an automatic acceptance decision. - Provider-specific parameters are retained by model overrides; switching to a provider with a different request contract may require an operator update. - These changes are included in 1.2.0. The complete release notes are in `CHANGELOG.md` under `1.2.0`. The validation below records the original migration work, not the full 1.2.0 release validation. No paid provider calls or ARC benchmark runs were made during that migration. ### Validation performed - `uv run pytest --cov --cov-report=term:skip-covered`: 1,274 passed, 85.47% coverage (repository threshold: 85%). - After the final default-parameter serialization compatibility fix: `uv run pytest tests/test_loader.py tests/test_evolution_reliability.py tests/test_truncated_turns.py`: 54 passed. - `uv run ruff check .` and `git diff --check` passed. - `uv build` produced both sdist and wheel; the wheel includes the evolution contract and guidance, and contains no ARC assets. - Isolated-home JSON CLI checks passed: schema emission, validation of `tests/fixtures/harnesses/example-summarizer` (current fixture location), and its `run --dry-run`.