A self-contained, deterministic validation engine for OpenSpec v1.1 specifications.

pip install crucible-forge  •  import crucible

---

crucible takes a software specification (with its epics and tickets), scores it against a fixed, configurable rubric, and reports a readiness gate — with no LLM, fully deterministic. Same input, same score, every time.

It is a faithful Python port of the SpecForge @specforge/validator engine, extracted as a standalone library, and is the planning gate of SpecSmither. The output is byte-equivalent to the reference TypeScript engine, verified by differential tests across every phase and output layer.

Why

• 🎯 Deterministic — pure scoring, no model calls. Reproducible in CI.
• 📦 Self-contained — pure Python; only pydantic and pyyaml at runtime.
• 🔬 Faithful — output matches the reference TS validator (differential-tested).
• 🎚️ Configurable — every threshold, tier weight, and check lives in config.
• 🏷️ Typed — ships py.typed; passes mypy --strict.

Install

pip install crucible-forge      # → import crucible
# or
uv add crucible-forge

Requires Python ≥ 3.11.

Quick start

from crucible import validate, load_defaults

result = validate(spec, {
    "phase": "planning_spec",
    "config": load_defaults(),                      # optional — loaded by default
    "returns": ["structural", "scoring", "guidance"],
})

if result.scoring and not result.scoring.skipped:
    print(result.scoring.gate_result)   # 'pass' | 'fail'
    print(result.scoring.local_score)   # e.g. 86.11
    print(result.passed)                # overall gate for the phase

# Canonical camelCase JSON (matches the reference engine):
result.to_json_dict()

spec may be a crucible.Specification model or a plain dict (camelCase, the OpenSpec v1.1 shape). The context accepts the original keys (phase, activeEntityId, config, returns) or their snake_case forms.

The model

A spec is a hierarchy:

Specification → Epic → Ticket  (+ acceptance criteria, impl steps, tests, files, dependencies)
                                    ↘ ticket dependency DAG ↙

validate() walks this tree and produces up to four output layers:

layer	what it reports
structural	schema issues — missing fields, format violations, duplicate orders, entity counts
scoring	the readiness score + gate (rubric tiers, weighted blocks, topology penalties, cascade floors)
crossValidation	cross-entity consistency — cycles, orphan/island tickets, file conflicts, wave coordination, blueprint coverage
guidance	human-readable, prioritized fix suggestions composed from the above

Request the layers you want via returns; a single phase returns whatever it computes, and phase: "all" defaults to ["scoring"].

Phases

validate() is driven by context["phase"]:

phase	scope	needs activeEntityId
planning_spec	spec-level fields
epic_decomposition	spec + the epic list
epic_expansion	one epic's fields	✓
ticket_decomposition	tickets under one epic
ticket_expansion	one ticket's fields	✓
cross_validation	full-tree consistency checks
all	every phase, keyed under by_phase

# Summative gate over the whole tree:
allr = validate(spec, {"phase": "all", "returns": ["scoring", "crossValidation"]})
planning_passed = (
    allr.by_phase["planning_spec"].scoring
    and allr.by_phase["planning_spec"].scoring.gate_result == "pass"
)

Structural-only

When you just need the schema check (no scoring/guidance):

from crucible import validate_structural, load_defaults

res = validate_structural(spec, load_defaults(), "planning_spec")
if not res.missing_fields and not res.invalid_fields:
    ...  # schema-clean

Configuration

Every gate is config-driven. load_defaults() returns the packaged ValidatorConfig (thresholds, tier weights, the 53-entry rubric thresholds, topology penalties, cross-validation rules). Layer overrides with merge_config:

from crucible import load_defaults, merge_config

config = merge_config(load_defaults(), {"thresholds": {"global": 85}})

The scoring rubric (53 entries: 16 spec · 17 epic · 20 ticket) ships as a data asset at crucible/guidance/rubric/data/rubric.json, generated verbatim from the reference source.

Public API

from crucible import (
    validate, validate_structural,            # entry points
    load_defaults, load_from_file,            # config loading
    load_partial_from_file, merge_config,
    CONFIG_DEFAULTS, ValidatorConfigSchema,
    PlanningConfigResolver,                    # project/spec config resolution
    ValidatorInputError,                      # raised on bad context
    Specification, Epic, Ticket, Blueprint,   # OpenSpec models
    models, types,                            # full model + result namespaces
)

Development

uv sync --all-extras --dev
uv run ruff check src tests
uv run mypy
uv run pytest                 # 125 tests, incl. differential vs the TS engine

Fidelity is verified against committed golden output captured from the reference engine, so CI needs no extra tooling.

Status

0.1.0 — a complete port, verified byte-for-byte against the current TS validator across every phase and all four output layers (structural · scoring · crossValidation · guidance).

License

Apache 2.0 © Gabriel Augusto Gonçalves / blacksmithers