20 short patterns for the questions CCPEDIA sees most: error diagnosis, version upgrade planning, party allocation, token transfers, validator ops, governance, dev fund proposal craft.
Problem. On a fresh Canton install the JSON Ledger API rejects submissions because no party has been allocated.
Solution. Call `/v1/parties/allocate` with a `partyIdHint` you control. Re-using the hint is idempotent; the participant returns the existing identifier.
curl -X POST $LEDGER/v1/parties/allocate \
-H "Authorization: Bearer $TOKEN" \
-d '{"identifierHint": "alice", "displayName": "Alice"}'Problem. Developers default to gRPC out of habit even when a browser-facing dApp would prefer JSON.
Solution. For browser/Node clients use JSON Ledger API v2 (simpler auth, streaming via SSE). For backend/services with tight latency use the gRPC API. Both expose the same domain model.
Problem. AI agents keep recommending `daml-assistant` / `daml start` long after they were retired by DPM.
Solution. Always call CCPEDIA's `check_deprecation` MCP tool before printing an install command. It returns DEPRECATED / CURRENT / NOT_FOUND with the replacement.
Problem. Stale tutorials still point to retired npm packages.
Solution. Use the current DA tooling exposed via `dpm codegen-js` (TS bindings) and the @canton-network/dapp-sdk for CIP-0103 wallet transport. Run `list_deprecations` to scan for any other names you might still be using.
Problem. Splice/Canton ship every 1–2 weeks; teams discover breaking changes only after CI breaks.
Solution. Run `get_breaking_changes(from, to)` against the target tags before bumping — it joins the GitHub release notes with forum activity in the post-release window so you see both the announced and observed regressions.
Problem. Curated KBs and tutorials lag the live release feed by weeks.
Solution. `get_current_versions` joins github_releases tags with validator-announce mailing-list posts. Cross-check static KBs against this before trusting them.
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 (incl. underscore-split parts) and searches forum_fts + github_items for prior resolutions.
// MCP call
diagnose_error({ error_text: "TOPOLOGY_TOO_MANY_PENDING_TOPOLOGY_TRANSACTIONS at submitPartyOnboardingTransaction" })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.
Problem. Custom transfer choices duplicate logic that the standard already covers.
Solution. Use the Canton Token Standard (CIP-0056) reference flows: `Transfer`, `TransferIntent`, `TransferReceipt`. Build new tokens by extending the standard, not replacing it.
Problem. CIPs sit in different states (Draft, In Review, Approved, Final) and may declare `Requires:` blockers that haven't shipped.
Solution. Call `detect_cip_dependency_chain(cip_id)` — returns the full prerequisite chain with each prerequisite's current status. ✓ = Final/Approved; ✗ = still blocking.
Problem. A live CIP debate happens in cip-discuss mailing + forum + GitHub at once; following one is partial.
Solution. `get_cip_citations(cip_number)` returns per-source backlinks with per-message granularity — including individual mailing messages, forum posts, GitHub items, blog posts, and videos.
Problem. Ops teams hit traffic freezes / topology freezes / synchronizer upgrades by surprise.
Solution. Subscribe to the SV calendar via `get_upcoming_operations(days)` or query `get_sv_schedule(environment="MainNet")`. The calendar is synced from sv-cal.canton.foundation every 12 hours.
Problem. Validator onboarding has many moving parts (topology, traffic balance, ValidatorLicense, sequencer).
Solution. Run `get_started_guide(background="enterprise")` for the structured path, then `get_sv_schedule(environment="DevNet")` to plan around the next upgrade. Cross-check `get_kb_drift()` so you're reading current values.
Problem. Dev Fund inbox routinely receives near-duplicate proposals (LocalNet tooling, validator runbooks, wallet abstractions).
Solution. Run `detect_builder_overlap(idea)` before drafting. Returns scored matches across 410+ proposals AND 458 ecosystem projects.
Problem. Approval depends on milestone clarity, named deliverables, scope realism — easy to miss in a first draft.
Solution. `proposal_success_predictor(draft_text)` walks a ten-point checklist (milestones, deliverables, sources, length, Apache 2.0…) and scores the draft. Aim for ≥80%.
Problem. The right Canton-side expert for "topology" or "wallet kernel" isn't obvious from forum username alone.
Solution. `find_expert(topic)` ranks authors by topic-relevant + total volume. Top forum posters skew toward DA engineering staff who maintain the affected component.
Problem. Foundation governance and many SV ops discussions never make it to the forum — they live on lists.canton.network.
Solution. `search_mailing_list(query, group?)` indexes cip-discuss, cip-vote, cip-announce, grants-discuss, validator-announce and globalSyncForum. Pass `group="cip-vote"` to drill into formal votes.
Problem. Builders working on adjacent capabilities (e.g. a wallet + a DEX + a bridge) rarely discover each other.
Solution. `find_collaboration_opportunities(project)` returns ecosystem_projects with overlapping tags/category. Use it once at proposal-time and again at design-time.
Problem. Forum threads contain working code but Google rarely surfaces them.
Solution. `find_code_examples(topic)` returns forum threads with embedded `<pre>`/`<code>` blocks matching the topic. Faster than reading the spec when you need a sketch.
Problem. The curated Foundation knowledge-base.json drifts behind live releases — and the maintainer can't scan everything themselves.
Solution. CCPEDIA runs `get_kb_drift` daily, then auto-opens PRs to canton-network-devs/Build-on-Canton-MCP with the corrections. Anyone can run `scripts/generate-drift-pr.ts --dry-run` to preview what would be submitted.
