Tessellum

Typed atomic notes in a graph — a Zettelkasten that scales.

Knowledge construction for humans and agents — typed atomic notes, a Building-Block type system, a one-way CQRS split, and a graph of Folgezettel trails, with a dialectic reasoning engine on top.

Tessellum is a knowledge-construction system, not an agent-memory store. Its unit of work is a typed atomic note — a tessellum, a small mosaic tile — small enough to make a single point, and tagged with what kind of point it makes. You author these notes yourself, or hand Tessellum a source document and let it digest the source into them. Either way, Tessellum indexes the notes and retrieves them with hybrid search (keyword and vector, combined). It lets you grow Folgezettel trails — chains of notes that record how one idea led to the next — and it runs a closed-loop reasoning engine, the Dialectic Knowledge System, that revises its conclusions as arguments and counter-arguments pile up. Underneath is a clean read/write split (the CQRS pattern): the notes you author are the source of truth, the searchable index is a projection rebuilt from them, and changes only ever flow one way — from the notes to the index, never back.

Quick Start

pip install tessellum

# 1. Scaffold a new vault (templates + seed term + master TOC)
tessellum init ~/my-vault
cd ~/my-vault

# 2. Capture your first typed atomic note — 14 flavors available
tessellum capture concept page_rank --vault .        # creates resources/term_dictionary/term_page_rank.md
tessellum capture skill my_skill --vault .           # creates a single self-contained skill_*.md
tessellum capture code_snippet my_algo --vault .     # creates resources/code_snippets/snippet_*.md
tessellum capture code_repo my_repo --vault .        # creates areas/code_repos/repo_*.md
tessellum capture --help                   # full flavor list

# 3. Validate format (closed-enum YAML spec)
tessellum format check .

# 4. Index the vault (notes + links + FTS5 + sentence-transformer embeddings)
tessellum index build --vault .

# 5. Retrieve — hybrid RRF default; --bm25 / --dense / --bfs for explicit strategy
tessellum search "graph traversal"
tessellum search --bm25 "PageRank"          # lexical only
tessellum search --bfs term_page_rank.md    # graph traversal from a seed
tessellum filter --tag concept --building-block model   # direct metadata filter

# 6. Compose — typed-contract runtime for skill-driven workflows
tessellum composer validate resources/skills/                                 # all skills
tessellum composer compile  resources/skills/skill_my_skill.md                # typed DAG, zero LLM
tessellum composer run resources/skills/skill_my_skill.md --vault .           # serial mock backend
tessellum composer run resources/skills/skill_my_skill.md --vault . --backend anthropic
tessellum composer run resources/skills/skill_my_skill.md --vault . --backend bedrock
tessellum composer run resources/skills/skill_my_skill.md --vault . --dynamic --workers 8 \
    --manifest run.json --close-gate --wave-gate --max-invocations 200
tessellum composer batch    jobs.json --parallelism 8                        # parallel multi-skill
tessellum composer eval     scenarios/  --judge-backend anthropic            # structural assertions + LLMJudge rubric
tessellum composer digest   --source source.json --vault .                   # digest one source: plan → augment → review → execute

# 7. DKS — run the Dialectic Knowledge System engine over observations
tessellum dks observations.jsonl --perspectives a,b,c                        # multi-cycle dialectic (N>2 → Dung)
tessellum dks --report                                                       # inter-cycle telemetry
tessellum dks --meta --apply                                                 # second-order: mutate the BB schema

# 8. Run automatic inbox digestion
tessellum runtime init
tessellum runtime serve --backend anthropic                                 # scan, lease, digest, commit

# 9. Serve tools to an agent over MCP (pip install tessellum[mcp])
tessellum mcp serve                                                          # stdio server, 12 tools

tessellum --version prints the version; bare tessellum prints the capability banner.

Status

Current main — every engine subsystem shipped. Test suite: 1389 passing, 1 skipped. Newest: the Composer v4 engine, the knowledge-transaction track, and the v5 automatic runtime.

• Composer — typed-contract pipeline runtime. A skill compiles to a typed DAG with zero LLM calls. It then runs serially or in parallel. Backends: Mock / Anthropic / Bedrock / Pooled.
• Knowledge transaction — a multi-note digestion as one atomic transaction. Staged, gated, then published all-or-nothing. Additive and opt-in.
• DKS — the Dialectic Knowledge System. It reasons, not just stores. Arguments meet counters; conclusions update from disagreement. A meta-layer even evolves the type schema.
• Retrieval — hybrid search over the graph. BM25 + vector (RRF fusion), plus graph traversal and metadata filters.
• Indexer — the vault as one SQLite database. Full-text + vector + link graph, rebuilt in a single pass.
• Format — the note validator. A closed-enum check of frontmatter, links, and building-block edges.
• BB — the Building Block ontology. 8 typed note roles, versioned and event-sourced. The source of truth for types.
• Automatic runtime — unattended, crash-safe digestion. A durable inbox queue with leased workers. Atomic index publication.
• Interfaces — for humans and agents. A 12-command CLI and a 12-tool MCP server.

See the CHANGELOG for the full per-release ship list.

Foundations & Capabilities

Tessellum rests on four foundations — remove any one and the system stops working. Its flagship features are built on top of them.

Foundations — what the whole implementation stands on:

Capabilities — built on those foundations:

Lineage. Tessellum descends from the Zettelkasten tradition (a slipbox of atomic, linked notes) and borrows PARA (Projects / Areas / Resources / Archives) as a filing convention. That is the ancestry; the foundations above are what this implementation actually stands on.

What Tessellum Is Not

Architecture

Source-level view of Tessellum's write and retrieval paths. Solid arrows are active runtime paths; dashed arrows identify opt-in primitives or integrations that are implemented but not wired into the automatic runtime end to end.

                    inbox sources (papers, drafts, PDFs, docs)
                                       │  digest: plan → augment → review → execute
                                       ▼
                    ┌──────────────────────────────────────┐
                    │  vault/  (markdown + YAML)           │
                    │  System P — typed substrate          │
                    │   • 8 BB types × ~80 sub-kinds       │
                    │   • PARA categories                  │
                    │   • Folgezettel trails               │
                    └──────────────────┬───────────────────┘
                                       │ indexed
                                       ▼
                    ┌──────────────────────────────────────┐
                    │  data/tessellum.db (one .db file)    │
                    │  SQLite + sqlite-vec + FTS5          │
                    └──────────────────┬───────────────────┘
                                       │ queried
                                       ▼
                    ┌──────────────────────────────────────┐
                    │  src/tessellum/retrieval/            │
                    │  System D — descriptive retrieval    │
                    │   • Hybrid BM25 + vector via RRF     │
                    │   • Best-first BFS + metadata filter │
                    └──────────────────┬───────────────────┘
                                       │ exposed
                                       ▼
                    ┌──────────────────────────────────────┐
                    │  Interfaces + runtimes               │
                    │   • CLI (12 cmds): init/format/      │
                    │     capture/index/search/filter/fz/  │
                    │     bb/composer/dks/mcp/runtime      │
                    │   • Composer v4: skill canonicals →  │
                    │     typed DAGs, serial or --dynamic  │
                    │     self-claiming scheduler;         │
                    │     backends Mock/Anthropic/Bedrock  │
                    │   • DKS engine: closed-loop dialectic│
                    │     over the BB graph (+ meta-DKS)   │
                    │   • MCP stdio server (shipped, 12    │
                    │     tools) + a composer-ts/ bridge   │
                    └──────────────────────────────────────┘

The loop closes through the vault. The Composer and DKS engines read the index (System D) and author new, connected notes back into the vault (System P); the next build re-projects them into the index. So knowledge flows from the vault, into the index, into new notes, and back to the vault — never around it. The automatic runtime drives this loop continuously (tessellum runtime serve). See docs/digestion.md for the source-to-notes flow and docs/architecture.md for the full deep dive.

The Building Block Ontology

Every tessellum has a building_block field in YAML frontmatter — one of 8 typed roles, each with a defining epistemic function. The typed edges between roles form a versioned, event-sourced schema graph (~16 edges: 8 epistemic + 7 navigation-index + 1 DKS extension) — the source of truth is src/tessellum/bb/, and the second-order meta-DKS can mutate it. This ontology drives the Dialectic Knowledge System. See vault/resources/term_dictionary/term_building_block.md and docs/bb.md.

Folgezettel Trails

Wikilinks tell you what's related. Folgezettel trails tell you how thinking developed — argument → counter → response → reframe → synthesis, encoded in trail IDs (7 → 7a → 7a1 → 7a1a). See vault/resources/term_dictionary/term_folgezettel.md.

Digestion — sources into connected notes

Tessellum doesn't only store the notes you write; it digests source documents into them. A digestion runs one pipeline of four phases — plan → augment → review → execute — and it does two things at once.

It decomposes the source into notes small enough that each makes a single point, one per building-block type. And it connects each note into the graph: back to the source it came from, up to the index pages that make it findable, across to its neighbouring notes, and into its place on a Folgezettel trail. A digested note is never dropped in as an island.

The plan is reviewed and gated before the authoring step runs, so an unsound decomposition never reaches the vault. The optional knowledge-transaction track goes one step further: it stages a whole digestion off to the side, proves it is sound, and publishes every note at once — all-or-nothing. See docs/digestion.md for the full flow.

Documentation

New here? The fastest path is to run the Quick Start above, skim Foundations & Capabilities for the mental model, then read the two docs that explain the system end to end.

• docs/digestion.md — how a source becomes connected notes: the plan → augment → review → execute flow, and how each note is wired into the graph.
• docs/architecture.md — the whole system in one picture: the CQRS wall between authoring and computation, the subsystems, and the invariants that keep each honest.
• docs/ — per-module design + reference docs (composer, dks, retrieval, indexer, bb, format, runtime, cli, mcp).
• vault/0_entry_points/entry_master_toc.md — the concept documentation itself, written as typed notes (Tessellum dogfoods its own format).
• CHANGELOG.md — per-release ship list. DEVELOPING.md — contributor guide and the two-surfaces rationale.

Project Structure

The top-level layout maps each folder to a defined CQRS role — System P (capture), System D (retrieval), or governance/runtime that sits outside both. See plans/plan_cqrs_repo_layout.md for the full workflow → folder mapping.

Tessellum/
├── src/tessellum/         Python code — engines for System P (capture) and System D (retrieval)
│   ├── bb/                Building Block ontology — 8-type, versioned, event-sourced schema graph (source of truth)
│   ├── format/            Validator + parser + BB-graph-aware link checker (closed-enum YAML spec)
│   ├── indexer/           Vault → one SQLite DB (notes + note_links + FTS5 + sqlite-vec; all-MiniLM-L6-v2 384-d)
│   ├── retrieval/         BM25 + dense + hybrid RRF + best-first BFS + metadata filter (+ heuristic router)
│   ├── composer/          Composer v4 runtime — compiler + scheduler (serial run_pipeline + dynamic
│   │                      run_pipeline_dynamic) + executor (retry ladder) + manifest + gates + fix +
│   │                      credential_pool + context_assembler + planning + signoff + llm
│   │                      (Mock/Anthropic/Bedrock/Pooled) + batch + eval
│   ├── dks/               Dialectic Knowledge System engine — core + fsm + dung + confidence + persistence + meta/
│   ├── runtime/           Durable automatic inbox queue, routing, leased supervisor, commit tail, and tool broker
│   ├── capture.py         14-flavor capture registry (concept, procedure, skill, model, argument,
│   │                      counter_argument, hypothesis, empirical_observation, experiment,
│   │                      navigation, entry_point, acronym_glossary, code_snippet, code_repo)
│   ├── init.py            tessellum init scaffold
│   ├── cli/               Per-subcommand dispatchers (12 commands) wired into argparse
│   ├── mcp/               Shipped MCP stdio server (12 tools) — `tessellum mcp serve`
│   └── data/              Force-included template directory + seed-vault content
├── composer-ts/           TypeScript orchestration bridge (bridge-not-port; shells the Python CLI)
├── docs/                  Architecture + per-module design reference
├── vault/                 Shared substrate — typed atomic notes (Tessellum dogfoods itself)
│   ├── 0_entry_points/    Master TOC + 5 acronym glossaries (statistics, critical thinking,
│   │                      cognitive science, network science, LLMs) + master glossary index
│   ├── resources/
│   │   ├── term_dictionary/   Conceptual primer (BB, FZ, DKS, CQRS, Z, PARA, …)
│   │   ├── how_to/            How-to guides
│   │   ├── analysis_thoughts/ Architecture arguments + FZ trails
│   │   ├── templates/         15 copy-and-fill skeletons (executable spec exemplars)
│   │   ├── skills/            Self-contained skill canonicals (per-step contract blocks inline)
│   │   ├── code_snippets/     `## Patterns`-format snippet notes (one component or algorithm)
│   │   ├── code_repos/        Repo notes (main + sub-note structure)
│   │   ├── teams/   tools/   faqs/   digest/   papers/
│   └── areas/             Code-repo notes (main + module sub-notes)
├── inbox/                 System P input queue — drop zone for raw incoming (papers, drafts)
├── plans/                 Governance — project-management plans (committed, top-level)
├── data/                  System D build output (gitignored, regenerable: DBs + embeddings)
├── runs/                  Both-system runtime traces (gitignored)
│   ├── capture/           Capture-pipeline traces (reserved; not yet wired)
│   ├── retrieval/         Retrieval evaluation + benchmark traces (reserved; not yet wired)
│   ├── composer/          Composer chain run traces (wired by `tessellum composer run/batch`)
│   └── runtime/           Durable jobs, content-addressed spool, artifacts, and source archive
├── experiments/           Experiment outputs
├── scripts/               Operational utilities (one-off migrations; not in wheel)
└── tests/                 Test suite (1389 passing, 1 skipped)

Two documentation surfaces, by audience. docs/ is the engineering reference — the system architecture, the end-to-end digestion flow, and a per-module design doc (runtime, composer, dks, retrieval, indexer, bb, format, cli, mcp) for contributors reading the code. vault/ is the knowledge documentation — Tessellum dogfoods itself, so its concepts, how-tos, and design arguments live as typed atomic notes; start at vault/0_entry_points/entry_master_toc.md. See DEVELOPING.md for the rationale.

Compared to Adjacent Tools

License

MIT — use freely, contribute back.

Origin

Tessellum is the public release of a typed-knowledge system originally developed inside a production research vault. The architecture (BB ontology, Folgezettel trails, DKS protocol, CQRS thesis) was discovered through ~14 long-running Folgezettel research trails over 2024–2026.

The name Tessellum is Latin: small mosaic tile — the atomic typed unit. A vault is the mosaic.

Acknowledgments

• The Zettelkasten community (especially Sascha Fast at zettelkasten.de) for the Building Block taxonomy this work builds on
• Niklas Luhmann for proving typed atomic notes scale to ~90k connected ideas
• Tiago Forte for the PARA scheme
• The Phasespace-Labs / palinode project for independently validating the SQLite + sqlite-vec + FTS5 + RRF stack
• CQRS architects (Greg Young, Udi Dahan) for the read/write split applied here to typed knowledge