v3.1.0

Spec v3.1.0

Spec change

tool field is now optional in the graph profile header. Previously required, now SHOULD be present for MCP tool responses but is not enforced. This enables non-MCP use cases (Neo4j queries, knowledge graphs, ontologies, agent memory) without inventing a tool name.

Conformance

• 157 fixtures (was 156): added graph-decode/003_no_tool_field.json, removed errors-v2/022_missing_graph_tool.json
• All 6 implementations at full conformance (157/157)
• 23.25B+ round-trips verified across 6 languages, zero failures:

Language	Round-trips	Status
Rust	23,000,000,000+	PASS
Go	200,000,000	PASS
TypeScript	20,000,000	PASS
Swift	20,000,000	PASS
Python	10,000,000	PASS
Kotlin	10,000,000	PASS

Bug fixes (all 6 implementations)

• Quote strings containing commas in scalar values
• Decode v2-format indented attachments in tabular rows
• Reject duplicate attachments on the same row
• Reject orphan attachments on rows without ^ cells

Playground

• Multi-format support: compare tab now accepts JSON, YAML, and TOML input
• TOON error state: TOON column shows red error panel for non-JSON inputs (TOON cannot encode YAML, TOML, or CSV)
• Encode tab: accepts JSON, YAML, TOML, CSV, and MessagePack (base64) input
• Decode tab: outputs as JSON, YAML, TOML, CSV, or MessagePack (base64)
• Presets for all formats including MessagePack binary data

Upgrade

All 6 implementations are releasing v2.1.0 with these changes. Drop-in upgrade, no breaking changes.

• Go: go get github.com/blackwell-systems/gcf-go@v1.2.0
• Rust: gcf = "2.1.0" in Cargo.toml
• TypeScript: npm install @blackwell-systems/gcf@2.1.0
• Python: pip install gcf==2.1.0
• Swift: update package dependency to 2.1.0
• Kotlin: update JitPack dependency to 2.1.0