diagrams-mcp-server

Technical Preview (V1 Preview, v0.7.0) — local-first MCP server for PlantUML and Mermaid diagrams: manage, render, and share them, check them against your codebase, and draft new ones from your code.

An MCP (Model Context Protocol) server that gives AI coding agents structured access to your project's PlantUML and Mermaid architecture diagrams. It can list, read, create, update, and delete diagrams, render and export them, check them against the codebase, diff two versions, and draft new diagrams from code or from starter skeletons — all locally, with no accounts and no network calls unless you explicitly opt in.

Works with any MCP-compatible client over stdio: Claude Code, Codex (Desktop & CLI), Antigravity (IDE, 2.0 & CLI), OpenCode (Desktop & CLI), Cursor, and VS Code. See Client setup below.

Why this exists

I built this after running into the same problem while using AI to work on software design. The diagram was in one place, the code was in another, and I kept having to paste context into the conversation. After a few rounds, it became hard to tell whether the diagram still described the project. I wanted a small local MCP server that could keep the diagram in the project, let the agent read it, and check it against the code when needed.

diagrams-mcp-server keeps diagrams in the project next to the code so an agent can read and check them in the same workflow. It uses the standard stdio MCP transport and does not require client-specific server code.

Related MCP server: scryer-mcp

Features

Twelve tools in four groups. The read-only drafting tools (diagrams_generate, diagrams_generate_sequence, diagrams_template, diagrams_export) never write: they return source text and you save it yourself with diagrams_create.

Manage diagrams

Render and share

Check and compare

Draft new diagrams

Tool notes

diagrams_check_consistency It reads entity names from class/interface/enum/component declarations, aliases, namespaces, packages, sequence participants, message calls such as charge(card), C4 blocks, and subgraph groupings. It then searches source files for matching identifiers, using declaration patterns for JavaScript/TypeScript, Python, PHP, and Java, and whole-word matching elsewhere. It helps detect common drift, such as a renamed or removed class or a component that has not been implemented. Structured output includes extracted, matched, and unmatched entities, per-entity file evidence, analyzer tiers, and an explicit heuristic confidence warning. The scan limits are listed under Consistency scan limits.

diagrams_generate

diagrams_generate is the generative flip side of that check: it reads the same declarations from a file or directory under your project root and drafts a class diagram from them — one box per declared name, plus extends/implements edges when the TypeScript compiler can evidence them. It is read-only and never writes: the source text comes back in the response, and nothing lands in diagrams/ until you save it with an explicit diagrams_create call. It is a heuristic (name extraction, not full type modeling): member lists, generics, namespace nesting, and cross-file inheritance through re-exports are out of scope, and a scope without TypeScript-family files yields entities with no relations and a dialect_note saying why. Every result is labeled confidence: "heuristic" with a heuristic_warning, and every cap reports itself in-band (entities_capped / entities_available / relations_capped / truncated), so a capped draft is never mistaken for a complete one. The generation limits are listed under Generation limits.

diagrams_generate_sequence

diagrams_generate_sequence drafts the other half of the picture: not the boxes, but the conversation between them. It reads the message-call patterns in a file or directory under your project root — one participant per scanned file, named by module — and emits ordered from -> to : message lines from the caller-to-callee edges the consistency checker's call graph already extracts. Static call-site order is not runtime order, and every result says so: a call inside a callback, promise, or listener is counted in deferred_count and excluded from the messages, because its real position in the conversation is unknowable from source. Participant mapping is declared-identifier equality only — a callee that no file in the scope declares is listed in unresolved_callees rather than attached to an invented participant, because which class owns a method is a type question and out of scope. Like diagrams_generate it is read-only and never writes — nothing lands in diagrams/ until you save it with an explicit diagrams_create call — and every result is labeled confidence: "heuristic" with a heuristic_warning, with every cap reporting itself in-band (participants_capped / messages_capped / *_available / *_limit / truncated). The sequence limits are listed under Sequence limits.

diagrams_diff

diagrams_diff answers the review-time question that follows an edit: what changed between two versions of the same diagram? Each side supplies exactly one of a stored path or inline text, so unstaged edits can be compared without a round trip, and the two sides may even use different dialects — each is read with its own syntax. It reports added / removed / renamed entity names, the unchanged list, and the sequence-side participants_* / calls_* fields ([], never absent, for class diagrams). Rename detection pairs a removed name with an added one only when the two are identical once lowercased and stripped of separators — the same shared normalizer the consistency checker uses to match names against code — so a genuine rename with a different spelling stays a plain add plus a remove, and every pair carries confidence: "heuristic". It compares declared names only: member lists, layout, and style are out of scope, and it never patches or merges — it reports, and you edit. Like the other read-only tools it touches nothing on disk; a malformed request is rejected before any file is read.

diagrams_template

diagrams_template is the blank-page tool that precedes all of them: give it a kind, a dialect, and the entity names, and it hands back a minimal skeleton that already clears every syntax gate. Boilerplate is where missing @startuml/@enduml boundaries and wrong starter keywords enter the repo, so one capped, deterministic emitter removes that failure mode: the six skeletons (class, sequence, C4-context × PlantUML, Mermaid) are fixed tables in source, and identical inputs yield byte-identical source in every process. It is pure — no filesystem, no code scanning, no heuristics, no state — so unlike diagrams_generate there is no confidence field and nothing to be uncertain about: it emits one declaration line per entity plus a TODO hint pointing at where the diagram grows, and nothing more. Member bodies, relations, and styling stay yours to write after the save. The PlantUML C4-context skeleton stays self-contained with plain rectangles, because real C4 shapes need the C4-PlantUML stdlib and this local-first server never fetches it; the Mermaid skeleton uses native C4Context. Nothing is ever written: the source comes back in the response, and nothing lands in diagrams/ until you save it with an explicit diagrams_create call. The template limits are listed under Template limits.

diagrams_export

diagrams_export is the sharing tool that closes the loop: package a stored diagram and its rendered SVG into one self-contained HTML file that opens anywhere, inside or outside the repo. It is packaging of two artifacts the server already produces — the stored source and the locally rendered SVG — so it adds no dependency (the HTML is string concatenation) and no new write surface: the tool never writes a file, the HTML comes back as text, and you decide where it lands. The artifact carries nothing external at all: no src/href URLs, no @import, no script, no web font — inline styles are the only styling, and the SVG is inlined as live markup rather than a base64 image, so it stays selectable and survives a strict content-security policy. The diagram's POSIX relative_path is the only path in the document. With include_source (the default), the source is embedded in a collapsible block built on the native <details> element, which needs no JavaScript; set it to false for a leaner file. Rendering follows diagrams_render exactly, including its CLI requirements and opt-in remote fallback, and rendered_with reports which path produced the image (local-plantuml / remote-plantuml / mmdc). A bundle larger than the byte cap is refused outright rather than cut down — truncated is always false, because a half-rendered artifact is worse than none. The export limits are listed under Export limits.

Pagination and source windows

Pagination is explicit and opt-in — the server never pages or truncates on its own.

diagrams_list accepts optional offset (non-negative integer, default 0) and limit (integer 1–500). Omitting both returns every match. The response always includes count (items in this page), total (matches before paging), the effective offset/limit, and has_more (whether items after this page remain). An offset past the end returns an empty page with has_more: false, not an error. Example: first diagrams_list({ "type_filter": "all", "limit": 10 }), then diagrams_list({ "type_filter": "all", "offset": 10, "limit": 10 }) while has_more is true.

diagrams_get accepts optional offset (zero-based character offset, default 0) and max_chars (integer 1–100000). Omitting both returns the full source. The response always includes is_partial, the effective offset, total_chars, returned_chars, and has_more; the text block always equals the returned content, so a window is never silently truncated. An offset past the end of the source returns an isError result instead of an empty string. Example: diagrams_get({ "relative_path": "models/big.puml", "offset": 0, "max_chars": 2000 }), then repeat with offset: 2000.

Requirements

• Node.js 18+ for running the server (runtime engines: >=18 — the compiled dist/ output, npm test, and npm start work on Node 18)

• Node.js >=20.19 for the development toolchain (npm ci, npm run lint, npm run format:check, npm run build) — the ESLint 10 toolchain does not run on older Node versions

• (Optional, for diagrams_render) @mermaid-js/mermaid-cli for Mermaid rendering: npm install -g @mermaid-js/mermaid-cli

• (Optional, for diagrams_render) A local plantuml CLI for offline PlantUML rendering. Without it, rendering fails with an actionable error unless remote rendering is explicitly enabled with ALLOW_REMOTE_PLANTUML=true, in which case it falls back to the public plantuml.com server over HTTPS. DISABLE_REMOTE_PLANTUML=true always disables the fallback, even when the allow flag is set.

Installation

You need Node.js 18+ — that is the only requirement. No accounts, no API keys, no separate services.

1. Get the package (pick one way)

Option A — no install (fastest way to try it)

npx diagrams-mcp-server --help

npx fetches the package on first use and caches it. Nothing is installed permanently, so this is the simplest way to try the server. The trade-off: the first run needs internet access, and MCP clients start the server fresh on every session — for daily use, prefer Option B.

Option B — global install (recommended for daily use)

npm install -g diagrams-mcp-server
diagrams-mcp-server --help   # prints the help text and exits 0

This puts a diagrams-mcp-server command on your PATH so any MCP client can launch it. To update later, just rerun the same command.

Option C — project dependency (pin a version per project)

cd /path/to/your/project
npm install diagrams-mcp-server
npx diagrams-mcp-server --help

Use this when different projects should use different server versions.

2. Connect it to your client

Installing the package alone is not enough: your MCP client also needs a diagrams entry telling it how to launch the server. The one-command setup writes that entry for you — no hand-editing JSON:

npx diagrams-mcp-server setup            # interactive: pick client, then scope
npx diagrams-mcp-server setup --client codex --yes   # non-interactive
npx diagrams-mcp-server setup --client cursor --scope project --yes   # pin this project

Setup asks for the client first, then the scope (each skippable with a flag):

• Global (Recommended): writes a clean entry with no PROJECT_ROOT — the server attaches to whatever directory the client launches it from. Best when you work across many projects.

• Project-specific: asks for the project root and bakes it in ("env": { "PROJECT_ROOT": "..." } for file-based clients, --env PROJECT_ROOT=... for claude/codex mcp add). Best when one config should always point at one project.

For file-based clients (Cursor, VS Code, Antigravity) this merges the entry into the client's config file. For Claude Code and Codex it runs their mcp add command; if that CLI is not installed, setup prints the exact command to run yourself. For OpenCode it prints the command to run. Restart file-based clients afterwards so they pick it up.

Setup opens with a version banner and runs pre-flight checks automatically: it warns when the claude or codex CLI is missing (printing the manual command instead), validates a project-scoped path (offering to create it), and ends with a summary of the client, scope, touched config, and status. Interactive prompts use arrow-key pickers (↑↓ + Enter, Esc cancels) and Yes/No toggles; manual commands appear in boxed cards, and status output is color-highlighted (plain text when piped or when NO_COLOR is set). Every prompt is skipped when the matching flag is passed.

3. Verify it works

Restart your client, then ask your agent: "List my diagrams." It should call diagrams_list — an empty list on a fresh project means everything is wired up correctly.

From source (contributors)

git clone https://github.com/mohammad-emad-dev/diagrams-mcp-server.git
cd diagrams-mcp-server
npm ci
npm run build
npm test

npm test runs the full suite from dist/ — unit, golden, and live-stdio integration tests that spawn the real server — so always build first. Before opening a PR, run all four gates: npm run build, npm test, npm run lint, npm run format:check (the last two need Node >=20.19).

Where the files live

• Global install (npm install -g diagrams-mcp-server): the package lands in the global node_modules (run npm root -g to find yours — e.g. C:\Users\<you>\AppData\Roaming\npm\node_modules on Windows, /usr/local/lib/node_modules on macOS/Linux) with launch shims on your PATH, so diagrams-mcp-server runs from anywhere.

• Project dependency (npm install diagrams-mcp-server inside a project): the same payload under <project>/node_modules/diagrams-mcp-server/, with the binary linked at <project>/node_modules/.bin/diagrams-mcp-server.

• npx diagrams-mcp-server: uses the global install if present, else the local one, else downloads and caches it — no manual file handling needed.

All three run the same entry point (dist/index.js), so MCP clients can use whichever path fits: the global shim, the project's .bin binary, or node <path>/dist/index.js directly.

Lint and formatting

npm run lint          # ESLint over src/ (TypeScript recommended rules, zero warnings allowed)
npm run format:check  # Prettier check over src/ (100-col, double quotes, semicolons, trailing commas)

Both run in CI (.github/workflows/ci.yml, Node 20.x/22.x matrix) before the build. They cover source and test files under src/ only — dist/, node_modules/, graphify-out/, and packed tarballs are excluded via eslint.config.mjs and .prettierignore. These two commands require the development toolchain (Node >=20.19); the server runtime itself still supports Node >=18. .gitattributes pins all text files to LF, so Windows and Linux checkouts produce identical line endings and the format check gives the same result on every platform.

Local tarball install without publishing

To install and run this Technical Preview from a local package file, create a tarball and install it in a separate consumer project:

npm pack   # runs the prepack build and writes diagrams-mcp-server-0.7.0.tgz
cd /path/to/your/project
npm init -y                       # if the consumer project has no package.json yet
npm install /path/to/diagrams-mcp-server-0.7.0.tgz
npx diagrams-mcp-server --help    # resolves the local install, exits 0

This installs only the published payload (dist/ runtime files, README.md, LICENSE) — no tests, fixtures, or local configs — and changes nothing outside the consumer project (no global packages and no registry publish). The package file is local, but npm may still download the package dependencies from the registry during installation. Point any stdio MCP client at the installed binary (node_modules/.bin/diagrams-mcp-server) the same way as dist/index.js in Client setup.

Uninstallation

Uninstalling has two independent parts: disconnecting the server from your client, and removing the package. Do either or both.

1. Disconnect it from your client

Delete the diagrams entry from your client's configuration and restart the client:

2. Remove the package

Match how you installed it:

npm uninstall -g diagrams-mcp-server   # global install (Option B)
npm uninstall diagrams-mcp-server      # project dependency (Option C, run inside the project)

If you only ever used npx (Option A), there is nothing to uninstall — optionally clear the download cache with npx clear-npx-cache.

What stays behind

Uninstalling never touches your diagram files: the diagrams/ folder in your project is your own work and is left exactly as it is. Delete it manually only if you want the diagrams gone too.

Client setup

diagrams-mcp-server speaks plain stdio MCP, so it works with any MCP-compatible client. Setup instructions for each below.

All examples assume you built the server at /absolute/path/to/diagrams-mcp-server and want it attached to a project at /absolute/path/to/your/project. Replace both paths with your own. If you installed from the registry, use the global install path or your project's node_modules/.bin/diagrams-mcp-server instead of a build directory (see Where the files live).

Claude Code

claude mcp add diagrams -- node /absolute/path/to/diagrams-mcp-server/dist/index.js

Set PROJECT_ROOT in your shell environment, or run Claude Code from within your project directory (it defaults to the current working directory).

Codex (Desktop & CLI)

codex mcp add diagrams -- node /absolute/path/to/diagrams-mcp-server/dist/index.js

Or add directly to ~/.codex/config.toml:

[mcp_servers.diagrams]
command = "node"
args = ["/absolute/path/to/diagrams-mcp-server/dist/index.js"]
env = { PROJECT_ROOT = "/absolute/path/to/your/project" }

Antigravity (IDE, 2.0 & CLI)

Antigravity IDE, Antigravity 2.0, and Antigravity CLI share one config file: ~/.gemini/config/mcp_config.json (or .agents/mcp_config.json for project scope). Add:

{
  "mcpServers": {
    "diagrams": {
      "command": "node",
      "args": ["/absolute/path/to/diagrams-mcp-server/dist/index.js"],
      "env": {
        "PROJECT_ROOT": "/absolute/path/to/your/project"
      }
    }
  }
}

You can also add it from the IDE: Agent panel → ⋯ menu → MCP Servers → Manage MCP Servers → View raw config, then paste the same block.

OpenCode (Desktop & CLI)

opencode mcp add

When prompted, choose Local as the server type and enter:

node /absolute/path/to/diagrams-mcp-server/dist/index.js

Or edit opencode.jsonc directly:

{
  "mcp": {
    "diagrams": {
      "type": "local",
      "command": ["node", "/absolute/path/to/diagrams-mcp-server/dist/index.js"],
      "environment": {
        "PROJECT_ROOT": "/absolute/path/to/your/project"
      }
    }
  }
}

Cursor (Desktop & CLI)

Add to ~/.cursor/mcp.json (global) or .cursor/mcp.json (project-scoped):

{
  "mcpServers": {
    "diagrams": {
      "command": "node",
      "args": ["/absolute/path/to/diagrams-mcp-server/dist/index.js"],
      "env": {
        "PROJECT_ROOT": "/absolute/path/to/your/project"
      }
    }
  }
}

VS Code (with GitHub Copilot)

Add to .vscode/mcp.json in your workspace:

{
  "servers": {
    "diagrams": {
      "command": "node",
      "args": ["/absolute/path/to/diagrams-mcp-server/dist/index.js"],
      "env": {
        "PROJECT_ROOT": "${workspaceFolder}"
      }
    }
  }
}

Or via the command palette: MCP: Add Server → Command (stdio), then enter the same command and args.

Configuration

Consistency scan limits

Every diagrams_check_consistency run observes these caps:

Generation limits

Every diagrams_generate run observes these caps. max_entities (1–60, default 30) bounds the emitted declarations; the limits below are the hard ceilings:

When the TypeScript compiler is not installed (published installs have no typescript dependency), the tool degrades openly instead of failing: entities still come from declaration patterns, relations is empty, and dialect_note says relations are unavailable.

Sequence limits

Every diagrams_generate_sequence run observes these caps. max_participants (1–20, default 8) bounds the declared participants and max_messages (1–50, default 20) bounds the emitted messages; the limits below are the hard ceilings:

When the TypeScript compiler is not installed (published installs have no typescript dependency), the tool degrades the same open way instead of failing: declared operations and call edges still come from the heuristic extractors, so participants and messages are still emitted.

Diff scope

diagrams_diff reports, and never silently drops a change — but it deliberately compares less than a differencing tool can:

The tool has no caps of its own: both sides are already bounded by the two sources being compared, so every added, removed, and renamed name is reported in full. It reads nothing outside the diagrams root, and input-shape errors (a side given both or neither of its path and content, or inline content in no recognized dialect) are reported before any file is opened.

Template limits

Every diagrams_template call observes these caps. There is no max_* argument to raise or lower — a skeleton is fixed scaffolding, so the ceilings below are the only shape it comes in:

Every name must match /^[A-Za-z_][A-Za-z0-9_]*$/ and no two may repeat — a duplicate would emit two declarations of the same box, so the second occurrence is rejected at its own index. A rejection comes back with isError: true and names the offending input; the emitted source always passes the same syntax gate diagrams_create applies, so a skeleton can be saved as-is.

Export limits

Every diagrams_export run observes this cap on the finished HTML document:

The SVG inside the bundle is bounded by what the renderer produced, and the renderer's own limits still apply on the way there. include_source is a boolean, not a size argument: the source block is either embedded in full or omitted, because a cut-off source next to a complete diagram would mislead a reader.

Example

diagrams/
└── models/
    └── user-class.puml

Ask your agent:

"Is the user-class diagram still accurate compared to the code?"

The agent calls diagrams_check_consistency, which reports:

1 of 2 entities in 'models/user-class.puml' were NOT found in the codebase:
- Order: 'Order' appears in the diagram but no matching identifier was
  found in the scanned codebase. It may be renamed, removed, or not yet
  implemented.

Project layout

src/
├── index.ts                       # Server entry point (stdio transport)
├── context.ts                     # Resolves PROJECT_ROOT / DIAGRAMS_DIR once at startup
├── constants.ts                   # Shared constants
├── types.ts                       # Shared TypeScript types
├── setup/                         # Guided client-setup wizard (scopes, pre-flight checks)
│   ├── index.ts                   # runSetup orchestrator
│   ├── clients.ts                 # Supported clients, arg parsing, config writers
│   ├── prompts.ts                 # Interactive pickers and confirmations
│   └── terminal.ts                # Banner, boxes, color
├── services/
│   ├── diagramStore.ts            # Safe filesystem CRUD (path-traversal protected)
│   ├── diagramValidator.ts        # PlantUML/Mermaid syntax checks and dialect detection
│   ├── nameNormalize.ts           # Shared lenient name normalizer (checker + diff)
│   ├── renderer.ts                # Mermaid/PlantUML -> SVG/PNG rendering
│   ├── scopeResolve.ts            # Bounds read-only tool scopes to PROJECT_ROOT
│   ├── consistencyChecker/        # Diagram <-> code drift detection
│   │   ├── index.ts               # checkConsistency orchestration (scan, match, report)
│   │   ├── entities.ts            # Entity names from diagram source
│   │   ├── codeAnalysis.ts        # Per-language declaration patterns
│   │   ├── scanning.ts            # Filesystem walk with scan limits
│   │   ├── sequence/              # Call-graph edges, participant mapping, message ordering
│   │   │   ├── callGraph.ts / operationIndex.ts / participantMapping.ts
│   │   │   ├── sequenceEntities.ts / sequenceMatch.ts / sequenceOrder.ts
│   │   │   └── sequenceGoldens.test.ts / sequenceOrderGoldens.test.ts
│   │   └── ts/                    # Optional TypeScript AST path (dynamic import only — never a static import, so published installs run without the compiler)
│   │       ├── tsParse.ts         # Compiler availability probe
│   │       ├── tsSymbols.ts       # Declared symbols + heritage collection
│   │       ├── tsIndex.ts / tsHeritage.ts  # Index and extends/implements edges
│   ├── diff/                      # diagrams_diff comparison
│   │   └── diffDiagram.ts         # Pure added/removed/renamed + sequence fields
│   ├── export/                    # diagrams_export bundle builder (pure, no filesystem)
│   │   ├── htmlBundle.ts          # One self-contained HTML string from SVG + source
│   │   └── exportGoldens.test.ts  # Exact wrapper structure locked per variant
│   ├── generate/                  # diagrams_generate entity collection and emitters
│   │   ├── collectEntities.ts     # Scan a scope into ordered entities + relations
│   │   ├── emitters.ts            # Pure PlantUML/Mermaid class-diagram emitters
│   │   ├── sequence.ts            # diagrams_generate_sequence orchestration (participants, messages, caps)
│   │   ├── sequenceEmitters.ts    # Pure PlantUML/Mermaid sequence emitters
│   │   └── scopeFiles.ts          # Scope walking shared by both generators
│   └── templates/                 # diagrams_template skeleton tables (no filesystem, no state)
│       ├── skeletons.ts           # Six pure emitters: kind x dialect
│       └── templateGoldens.test.ts # Exact emitted source per (template, format)
├── tools/                         # One MCP tool adapter per file (12 tools) + shared toolError/toolOutput
└── integration/
    └── mcpServer.test.ts          # End-to-end server surface tests

Tests live next to the source they cover (*.test.ts), compile to dist/, and run from there — npm test uses the file list in package.json, so new test files need adding there.

Security notes

• All file operations are restricted to the configured diagrams directory; attempts to read/write outside it (e.g. via ../..) are rejected. Windows-style \ separators work as path separators on every platform, so ..\.. traversal is rejected on Linux too.

• diagrams_check_consistency, diagrams_generate, and diagrams_generate_sequence only read your codebase — they never modify code or diagrams. Both generators resolve their scope against PROJECT_ROOT and refuse (without reading anything) any path that would land outside it; their output is source text you save yourself with diagrams_create.

• diagrams_diff is read-only too: stored sides are read through the same traversal-protected store as diagrams_get, inline sides never touch the filesystem at all, and input-shape errors are reported before any file is opened. Errors and logs never include diagram source, only the names being reported.

• diagrams_template touches no filesystem at all — no project root, no diagrams directory, no state between calls. It is pure source text in and out, so there is nothing to restrict and nothing to leak; the entity names you pass are the only thing it echoes back.

• diagrams_export reads one diagram through the same traversal-protected store as diagrams_get and returns the bundle as text — it writes nothing, so the store's extension allow-list never opens to .html. The artifact is built to be shared: it contains no external resource of any kind (no src/href URLs, no @import, no script, no font), and the only path it carries is the diagram's POSIX relative_path. Remote PlantUML rendering, when you opt into it, sends diagram source to the configured server; that is the renderer's existing path, unchanged.

• No credentials or external accounts are required for any tool. diagrams_render for PlantUML never leaves the machine unless remote rendering is explicitly enabled with ALLOW_REMOTE_PLANTUML=true — and never when DISABLE_REMOTE_PLANTUML=true is set, which takes precedence. Mermaid rendering never leaves the machine.

• Local renderer processes run with a timeout and bounded stdout/stderr capture (1,000,000 characters per stream, enforced while collecting). A renderer that exceeds the cap or its timeout budget is stopped: its output pipes are closed and the process is killed, and rendering fails with an actionable error that never includes captured output, paths, or environment values. On timeout, the error is delivered immediately rather than waiting for a descendant process that inherited the renderer's output pipes (for example through the Windows cmd.exe shim chain) to release them.

Roadmap

Shipped in v0.7.0 (see RELEASE_NOTES.md):

• TypeScript AST path for consistency checking — stricter matching plus extends/implements edges when the compiler is available, open heuristic fallback when it is not

• Sequence diagrams both ways: diagrams_generate_sequence drafts them from call-graph edges, and the checker compares message ordering (callbacks deferred, never sequenced)

• Diagram diffing (diagrams_diff), starter skeletons (diagrams_template), and self-contained HTML export (diagrams_export)

Still open:

• Code-from-diagram scaffolding: generate a class skeleton from a diagram (the reverse of diagrams_generate)

• AST-backed precision for more languages, as demand dictates

• Export hardening follow-up: allowlist SVG sanitizer for bundled markup (tracked in docs/next-features.md)

Contributions and issues welcome.

License

MIT — see LICENSE.