Cage Containment Receipt 1 (CCR-1): Deterministic Gate Blocks Invalid LLM Proposals Before Execution Across Four Engines

Cage Containment Receipt 1 (CCR-1): a deterministic execution gate rejected 100% of contract-invalid proposals before any side effect executed, while admitting only contract-valid actions to a harmless local mock target. Holds and escalations never caused side effects. This is the execution-containment complement to the PENTA-CL model-attribution replay evidence: matching decisions and blocked invalid proposals under the same deterministic envelope.

Results (falsifiers 0/5 tripped): 17 candidates = 1 positive control + 8 fresh LLM-generated captures (4 engines x 2: Claude Opus 5.5, GPT-5.6 Luna, GPT-6.1 Sol, GLM 5.2) + 8 harness-generated adversarial mutations. All 9 valid candidates admitted (72 actions written, 18 holds, 18 escalations — zero hold/escalation side effects). All 8 adversarial cases rejected with the mock journal hash unchanged: malformed JSON, case-normalized anomaly types, invented playbook ids, under-confidence heals, false holds, extra keys, wrong array length, duplicate positions. Duplicate action-id suppression and the hold/admit distinction (holds never increment the healing-action counter) verified.

Scope (honest limits): proves the local mock-gate for the tested integration and inputs only — NOT containment of every Base44 tool, any production runtime, or untested inputs. The adversarial mutations are harness-generated and labeled as such; no fresh adversarial-LLM conversation was created inside the run itself (that leg remains open). Small-scale sequential timing baseline included as descriptive n=1-2 data (no capacity claim). Dual Mesh Benchmark: NOT MEASURED.

Method operates under filed application 64/119,191 (Deterministically Governed Probabilistic Neural Computation); no unfiled-method disclosure is made. Two-key curation: Gabriel vetted, Leon approved (Oct 10, 2026).

This software is a prototype and is provided for educational and research purposes only. It is not intended for production use, commercial deployment, or safety-critical environments. All systems are experimental and may contain defects on them.

Related: PENTA-CL interim (10.5281/zenodo.23286324), PENTA-CL v2 replay (10.5281/zenodo.23286770), First Documented Caging of an LLM (10.5281/zenodo.23265723), Deterministic Caging paper (10.5281/zenodo.23266727), SDR-CL1 (10.5281/zenodo.23274887), SDR-CL2 (10.5281/zenodo.23284295). Ledger: https://github.com/LLong2026/four-horsemen. Community: https://zenodo.org/communities/dcai