src/pqc_reasoning_ledger/errors.py
| 1 | """Exception hierarchy for pqc-reasoning-ledger.""" |
| 2 | |
| 3 | from __future__ import annotations |
| 4 | |
| 5 | |
| 6 | class ReasoningLedgerError(Exception): |
| 7 | """Base exception for all pqc-reasoning-ledger errors.""" |
| 8 | |
| 9 | |
| 10 | class ChainBrokenError(ReasoningLedgerError): |
| 11 | """Raised when a step's previous_step_hash does not match the current chain tip, |
| 12 | or when step ordering/linkage is otherwise inconsistent.""" |
| 13 | |
| 14 | |
| 15 | class StepVerificationError(ReasoningLedgerError): |
| 16 | """Raised when a step's declared step_hash does not match its recomputed hash.""" |
| 17 | |
| 18 | |
| 19 | class TraceSealedError(ReasoningLedgerError): |
| 20 | """Raised when attempting to append to a trace that has already been sealed.""" |
| 21 | |
| 22 | |
| 23 | class InvalidStepError(ReasoningLedgerError): |
| 24 | """Raised when a step is structurally invalid (bad kind, bad confidence, etc.).""" |
| 25 | |
| 26 | |
| 27 | class StepNotFoundError(ReasoningLedgerError): |
| 28 | """Raised when a referenced step_id does not exist in a trace.""" |
| 29 | |
| 30 | |
| 31 | class SignatureVerificationError(ReasoningLedgerError): |
| 32 | """Raised when a SealedTrace's ML-DSA signature fails to verify, |
| 33 | or a full verification result is not fully_verified.""" |
| 34 | |