Local dashboard

A read-only Next.js dashboard, served by a FastAPI sidecar bound to 127.0.0.1, that visualises PII coverage, refused tool calls, and the tamper-evident audit chain over the same SQLite store the MCP server uses.

Local dashboard

One-line claim: schemabrain dashboard boots a FastAPI sidecar on 127.0.0.1:7878 that serves a pre-built Next.js static export. The UI reads from the same SQLite store + mcp_audit table the MCP server writes to. No Node runtime, no network exposure, no write paths.

The dashboard answers three operator questions that the MCP envelope alone does not surface visually:

1. Which entities carry catastrophic-leak PII categories? — see PII matrix.
2. What did SchemaBrain refuse, and what envelope did the agent receive? — see Refusals.
3. Is the hash-chained audit log still intact? — see Audit Viewer.

SchemaBrain renders nine read-only surfaces over that same store. The signature surface is the Knowledge Graph — your schema as the entity-relationship projection the semantic layer compiles joins against.

Knowledge Graph — entities as nodes, canonical joins as edges, catastrophic-PII entities flagged, and the compiled join path traced.

Overview — the whole boundary on one screen: bound entities, catastrophic-PII floors, refusals, and audit-chain health, each panel opening its detail view.

Entities — every business entity bound out of the raw schema, with PII exposure, binding confidence, metrics, and join counts.

Data Dictionary — every table, column, type, PII class, and join, exportable to Markdown for your repo or wiki.

PII matrix — one row per classified column across the 12 PII categories, each tagged block / redact / allow; catastrophic columns are hard-blocked regardless of policy.

Refusals — every held call; expand a row to reveal the reason that fired, the blocked category set, the recovery hint, and the reconstructed envelope.

Audit Viewer — the tamper-evident chain spined by a derived Merkle root, re-walked and verified intact down to each row's inclusion proof.

Policy — the block / redact / allow grid the firewall enforces, with the always-on catastrophic-leak floor disclosed and the schemabrain.yaml it compiles.

Drift — config and enrichment drift the store can detect, each with a copy-the-CLI fix; here, a fresh and in-sync context.

It is intentionally a viewer, not a console. No settings, no entity editor, no SQL pad. Configuration still lives in the CLI; YAML still lives on disk.

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Install

The dashboard ships as an opt-in extra so the base install stays slim and free of web-server dependencies (fastapi, uvicorn, sse-starlette).

pip

pip install 'schemabrain[ui]'

uv pip install 'schemabrain[ui]'

The pre-built Next.js static export is bundled inside the wheel at schemabrain/dashboard/static/. End users never need Node, npm, or pnpm. Contributor-dev runs are different — see the repo’s web/README.md.

A base pip install schemabrain will not boot the dashboard. Running schemabrain dashboard without the [ui] extra exits with schemabrain dashboard requires the [ui] extra. Install with 'pip install schemabrain[ui]'. and a non-zero exit code.

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Launch

Index your database first (or run schemabrain init), then point the dashboard at the same store:

schemabrain dashboard --store-path ./schemabrain.db

You should see:

schemabrain dashboard: serving at http://127.0.0.1:7878/
  press Ctrl+C to stop

The default browser opens automatically. Pass --no-open in CI or on headless machines to skip the auto-open.

Flags

Flag	Default	Purpose
--store-path PATH	./schemabrain.db	SQLite store written by schemabrain index. The sidecar auto-resolves the canonical source_id from this store.
--port N	7878	TCP port to bind on 127.0.0.1. Must be in the user-port range (1024-65535).
--no-open	(off — auto-opens)	Skip launching the default browser. Use in CI / headless environments.

There is no --host flag — by design. The bind host is a constant in schemabrain/dashboard/sidecar.py (BIND_HOST = "127.0.0.1"). The dashboard is local-only, full stop. Use SSH port-forwarding if you need to view a remote instance.

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What the sidecar exposes

The FastAPI app declares only GET routes. There is no POST, PUT, PATCH, or DELETE handler anywhere in the surface — a CI invariant test asserts this against the live route table.

Route	Purpose
GET /	Serves the bundled Next.js static export (the UI itself).
GET /api/health	Liveness + a SELECT 1 probe against the SQLite store.
GET /api/meta	Charter version, dashboard schema version, list of indexed sources. Credential-safe — connection URLs are hashed to a canonical short ID before being echoed.
GET /api/entities/pii-matrix	Per-entity PII category counts + totals for the PII matrix surface.
GET /api/entities	Flat entity list.
GET /api/entities/{name}/columns	Per-entity column drill-down (physical schema + metrics + canonical joins).
GET /api/audit/rows	Paginated rows from mcp_audit.
GET /api/audit/rows/{id}	One audit row with full body.
GET /api/audit/verify	Re-walks the chain hash; returns intact or broken.
GET /api/audit/merkle/root	Derived RFC-6962 Merkle root over every row (tree_size, root_hex).
GET /api/audit/rows/{id}/proof	O(log n) inclusion proof so the browser can reconcile a row to the root.
GET /api/audit/refusals	Filtered list of status='refused' rows.
GET /api/audit/refusals/{id}	One refusal row with envelope detail.
GET /api/audit/stream	Server-Sent Events stream for live row push (2s tick).

Every JSON response carries two headers:

• X-Schemabrain-Charter-Version: 1.2 — the MCP envelope contract.
• X-Schemabrain-Dashboard-Schema: 1.5 — the dashboard JSON contract.

Consumers can detect protocol drift without parsing the body.

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How source resolution works

The useSourceId() hook on the client and the _resolve_source() helper on the server share one rule: the dashboard never hardcodes a source ID. Resolution order:

1. If the request includes ?source_connection_id=..., use it.
2. Else, if SidecarConfig.source_connection_id was set at boot, use it.
3. Else, ask the store for list_distinct_source_connection_ids() and pick the first.
4. If the store knows about zero sources, return null and let the UI render an empty state.

This means a freshly-installed schemabrain[ui] against a previously-indexed store “just works” — no flag plumbing required.

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What the dashboard is not

• It is not a write surface. The sidecar declares no mutating verbs. The UI has no inputs that POST.
• It is not a SQL console. SchemaBrain does not execute arbitrary SQL anywhere — see /mechanism/read-only. The dashboard inherits that posture.
• It is not network-reachable. The bind host is hardcoded to 127.0.0.1. There is no flag, env var, or config file that changes this.
• It is not authenticated. Because it binds to localhost, the dashboard relies on OS-level user isolation. Don’t run it on a shared multi-user machine without thinking through who owns 127.0.0.1.
• It is not a settings editor. Curate entities, metrics, and joins via the CLI. The dashboard reflects state; it does not edit it.
• It does not include an entity browser. Editable entity workflows are post-v0.4.

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Related

PII matrix

Which entities and columns carry catastrophic-leak categories.

Refusals

Live feed of refused tool calls + the envelopes the agent received.

Audit Viewer

Tamper-evident audit chain, with one-click verify.

schemabrain dashboard CLI

Flags and defaults for the launch command.