
Product turns your features, architectural decisions, and test criteria into a queryable knowledge graph that Claude can navigate and update directly. The MCP server exposes the full CLI surface: feature lookup, context bundling, drift detection, gap analysis, and atomic writes via the request API. Instead of pasting six files into a chat to explain what changed three weeks ago, you let the agent call product_context with a feature ID and pull the exact ADRs and tests that govern it. The author commands go further, spawning Claude with read access to your entire graph so it can propose new features grounded in existing decisions rather than inventing from scratch. If your project has more than one decision worth remembering and you're tired of manually assembling context for every coding session, this is the missing layer between your markdown files and your agent.
A CLI and MCP server for the Product Framework — specify software as a verifiable What/How graph.
The Product Framework is an open standard for describing a software product as one connected, machine-readable graph: the What (domain model + event model — entities, commands, events, read models, UI steps typed against Abstract Interaction Objects, systems, triggers, Deciders, Projectors), the How (contracts, the screen-composition / reification model, delivery features), and the typed links between them. The graph can drive generation, gate verification, and explain itself — so "describe this system" is a query, not a stale document.
This repo is the reference tooling: a single Rust binary (product) plus an MCP
server that lets an agent author and verify the graph directly. No database, no
service — the graph lives as YAML/Turtle under .product/.
$ product init --demo # scaffold + seed the bookstore What model
$ product domain new system sys-shop --system-kind application \
--purpose "consumer e-commerce" --target-classes gui
$ product domain validate --strict # per-node shapes + graph-level completeness
$ product decider derive Order # derive an aggregate's executable signature
$ product decider validate Order-decider
$ product mcp --http # MCP server + a live Event-Modeling web view at /
# from source
cargo install --path product-cli
The binary ships with the What→How→Build Claude Code skills baked in.
product init writes them into .claude/skills/ of the new repo (pass
--no-skills to opt out); product skills install (re)installs them, and
product skills install --global puts them in ~/.claude/skills/ for every
project. Start a fresh Claude Code session to pick them up, then /product-session.
product session start (and product author domain) host the What→How→Build
session in an agent CLI — Claude Code or GitHub Copilot CLI. The CLI is
resolved in this order:
--cli claude|copilot flag, else[author].cli in .product/config.toml, else$XDG_CONFIG_HOME/product/config.toml
(or ~/.config/product/config.toml), elseclaude.# .product/config.toml — make this repo default to Copilot CLI
[author]
cli = "copilot"
Scaffold it on a new repo with product init --cli copilot, or set a personal
default for every repo by putting the same [author] block in
~/.config/product/config.toml. With a default configured, product session start needs no --cli flag.
product init --demo # a worked What model to explore
product domain list # the captured nodes, by kind
product domain show Order # one node and its links
product domain export # the graph as RDF/Turtle
product domain validate # §3.1/§3.2 per-node conformance shapes
product domain validate --strict # + §3.2.0/§3.2.5/§3.4/§4.5 completeness checks
product decider derive Order # §3.3 — derive decide/evolve signature
product decider simulate Order-decider # run its flow-derived scenarios
product guide # where you are + the next step
product domain … captures the domain + event model; product decider … (§3.3) and product projector … (§3.4) make behaviour and read
models executable; product primitive … (§3.5) names irreducible algorithms.product how, product feature, product build, product seam,
product preview cover the How contract, delivery features, the screen seam, and
the §11/§12 design-system / content-store preview profiles.product domain export).product mcp --http starts the MCP server (framework tools: product_domain_*,
product_decider_*, product_projector_*, …) and serves a live web view at /
that renders the active What graph across three connected views — Systems
(the product → systems & journeys map, §3.0), Domain (one bounded context as
an ER graph, §3.1), and Flows (a system's event-model as Event-Modeling
swimlanes — triggers / commands / views over per-aggregate event streams, §3.2).
A node detail panel, the What→How→Build phase stepper, dark/light theme and live
SSE refresh round it out.
The workspace also ships ddd (crates ddd-core, ddd-lsp, ddd-mcp,
ddd-cli), a separate tool over a separate store: a repo-local .ddd/ graph
of predicates, closure claims, decisions, analyzer/linter manifests, pattern
instances, seam declarations, and interception event rows
(spec, umbrella PRD, formats: migrations).
cargo run -p ddd-cli -- init # scaffold .ddd/
ddd validate # schema + ontology rules (CI gate)
ddd diff --sarif build.sarif # declared vs. detected rules (CI gate)
ddd report escapes # diff + cadence + basis-loss report, each section stating its coverage
ddd why CA2007 # rule -> decision -> principal -> claims (or: detected but unfiled)
ddd render # static self-contained HTML projection of the graph
ddd serve # the ddd_* MCP surface (stdio)
ddd warmup # pre-load the LSP hosts (Roslyn solution load)
ddd what # What-graph boundaries carrying no declaration
ddd what treats the .product/ What graph as a third governed surface
alongside C# and Bicep. It needs no language server: product-core already
owns the What as typed data, so the adapter reads kinds and containers
straight off DomainGraph and runs them through the same policy-table
mechanism (ddd-core/src/surface.rs, shared with the LSP adapters).
Two kinds of row. Boundary kinds are surface whatever they connect to: a system (§3.2.5), a context mapping (§3.1), a journey crossing (§3.0.1), a quality demand (§3.6). Published kinds are surface only when a §3.2.0 Translation carries them — the View a Translation watches, the Command it issues, and the Events that View projects. Everything else is internal to its own system and never demands a declaration.
That published/internal split is the What's analogue of C# visibility, and it
is load-bearing: the first table called every event and command a boundary,
which the measurement in DDD-what-02 killed (0 of 39 crossed anything). See
dec/ddd/what-published-qualifier.
A boundary counts as governed when a seam declaration's contract_location
is what:<element-id>. --strict turns it into a CI gate; the default
reports without failing, so the table can be calibrated against a real graph
first.
ddd serve exposes the ddd_* tool namespace over stdio: LSP-backed
language intelligence for C# (roslyn-language-server --stdio --autoLoadProjects, the official prerelease .NET global tool) and Bicep
(bicep-ls from Azure.Bicep.LangServer) — find_symbol, references,
hover, diagnostics (joined to the manifests by rule id, the same join the
SARIF path uses), signature, rename (computes; application funnels
through the interceptor) — plus the governance tools why, graph_query,
declare_seam, declare_pattern, accept_risk.
The three declare/accept tools take amend: true to revise an entry
already filed. The flag is explicit in both directions — a create never
silently overwrites, an amend never silently creates — and the split is by
field: judgement amends (verdict_knowledge, obligation answers, rationale),
while identity and LSP-derived evidence (contract_location, metadata) are
carried forward untouched, so the interception rows stay machine-authored.
ddd_apply_edit runs every edit through the per-language contract-surface
classifier (policy tables, PRD §9): non-surface edits apply; a surface edit
applies only with a matching same-session declaration; otherwise it is
rejected with a structured demand whose facts (symbol, kind, signature,
visibility, reference count) are pre-filled and whose judgment fields are
blank (dec/ddd/rejection-facts-prefilled). Modes: intercept: enforce | warn | off, per artifact class via intercept_by_class (config format 3);
adapter.csharp.internal_is_surface flips the library-repo posture
(dec/ddd/internal-not-surface). Every classified surface outcome lands as a
row under .ddd/seams/events/ — the correspondence dataset. Hosts are
spawned lazily, health-checked, and respawned on crash; while Roslyn loads
the solution, tools return an explicit {"status": "loading"} rather than
hanging. CI runs against a fixture-grade mock host
(dec/ddd/fixtures-not-sdk); set DDD_LSP_E2E=1 with both tools on PATH to
run the gated real-host suites.
ddd diff compares the manifests under .ddd/manifest/ against two detected
sources per language and reports UNGOVERNED (detected, no manifest entry),
STALE (manifest entry, absent from config and emissions), and
UNCITED_SUPPRESSION (a config or in-source suppression with no
risk-acceptance record):
configured — parsed from .editorconfig (dotnet_diagnostic.<ID>.severity
lines only; section globs are recorded, never evaluated — deliberately not an
editorconfig engine), bicepconfig.json (analyzers.core.rules levels), and
the root Cargo.toml ([workspace.lints.clippy], for this repo's own gates).
Rules enabled by analyzer-package defaults have no config line and surface
via the emitted source only — diff says so when one source covers a rule.
emitted — SARIF 2.1 files from real builds, ingested by one shared module. Produce them with (verified against current tool docs at M2):
dotnet build -p:ErrorLog=diag.sarif%2Cversion=2.1 — the MSBuild
ErrorLog property; version=2.1 is required (the default is SARIF 1.0),
and %2C escapes the comma on the CLI (or set <ErrorLog> in the project).bicep lint main.bicep --diagnostics-format sarif > bicep.sarif
(also available as az bicep lint).In-source suppressions differ per toolchain: the C# compiler still logs a
#pragma-suppressed diagnostic into SARIF (marked suppressed), which is how
UNCITED_SUPPRESSION sees it; Bicep's #disable-next-line removes the
diagnostic from the output entirely, so Bicep source suppressions are
invisible to detection — only level: off config suppressions are covered.
Point ddd diff at the files with --sarif or the detect.sarif list in
.ddd/config.yaml. This repo governs itself: .ddd/manifest/clippy.yaml maps
clippy::unwrap_used to its decision, and ddd diff verifies it against the
workspace lints table.
cargo build
cargo t # full suite (alias: test --no-fail-fast)
cargo clippy -- -D warnings -D clippy::unwrap_used
See CLAUDE.md for the architecture and contributor workflow, and docs/product-framework-open.md for the spec.
See LICENSE.