Error Reference

Xian surfaces errors from a few distinct layers. Knowing which layer produced the error makes debugging much faster.

Linter Errors

The contract linter reports structured Rust compiler diagnostics. Semantic rules use xian.lint.E###; parser, IR, and admission-limit failures use xian.syntax.*, xian.ir.*, and xian.limit.* respectively. These include:

• forbidden syntax
• illegal imports
• invalid decorators
• invalid type annotations
• nested function definitions

See:

• Valid Code & Restrictions
• Linter

Transaction Validation Errors

These happen before execution, during mempool admission:

• invalid signature
• wrong chain_id
• nonce mismatch
• insufficient balance for the supplied chi limit on paid-fee networks
• submitted chi above the configured 0-fee transaction or block cap

These transactions do not enter the block execution path.

Runtime Execution Errors

These happen during contract execution:

• failed assert
• out-of-chi
• runtime exceptions

Execution outputs also classify these failures under error_class:

• contract_assertion: a contract assert failed
• contract_error: another contract-level exception escaped
• chi_exceeded: execution ran out of chi budget
• call_limit_exceeded: the deterministic instruction/call cap was hit

Effects:

• state changes for that transaction are rolled back
• consumed chi are recorded; paid-fee networks charge the matching execution fee
• emitted events from that transaction are discarded

Query/Service Errors

Optional services can also fail independently:

• dashboard unavailable
• BDS disabled, catching up, or unavailable for indexed/history reads
• GraphQL unavailable because BDS is not running
• RPC or WebSocket connection failures

Those are operational errors, not consensus errors. Raw current-state ABCI queries can be healthy even when BDS-backed indexed reads are degraded or catching up.