Design patterns
Debugging
2 Canton design patterns for debugging.
Resolve a gRPC error code
Problem. You hit a Canton gRPC error like
UNAVAILABLE or TOPOLOGY_TOO_MANY_PENDING_TOPOLOGY_TRANSACTIONS with no obvious cause.Solution. Paste the full status into diagnose_error. The tool extracts distinctive tokens, including underscore-split parts, and searches forum_fts and github_items for prior resolutions.
// MCP call
diagnose_error({ error_text: "TOPOLOGY_TOO_MANY_PENDING_TOPOLOGY_TRANSACTIONS at submitPartyOnboardingTransaction" })References:
Diagnose a Canton bug right after a Splice cut
Problem. New Canton errors right after a Splice tag often turn out to be Splice-side, not Canton-side.
Solution. Pull get_recent_deployments() to see the freshest releases, then get_breaking_changes(from, to) against the relevant pair. Forum activity in the +14d window is usually the smoking gun.
References: