Selvedge

Long-term memory for AI-coded codebases. A git blame for AI agents — but for the why, not just which line which model touched. Captured live, by the agent, as the change happens.

Selvedge is a local MCP server. AI coding agents (Claude Code, Cursor, Copilot) call it as they work to log structured change events with reasoning. Your data stays in a SQLite file under .selvedge/ next to your code.

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Six months ago, your AI agent added a column called user_tier_v2. You don't know why. git blame points to a commit from claude-code with a generated message that says "Update schema." The session that made the change is long gone — and so is the prompt that produced it.

With Selvedge, you run this instead:

$ selvedge blame user_tier_v2

  user_tier_v2
  Changed     2025-10-14 09:31:02
  Agent       claude-code
  Commit      3e7a991
  Reasoning   User asked to add a grandfathering flag for legacy free-tier
              users during the pricing migration. Stores the original tier
              so we can backfill discounts without touching billing history.

That reasoning was captured by the agent in the moment — written into Selvedge from the same context that produced the change. Not inferred from the diff afterward by a second LLM. Not a hand-typed commit message.

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Who Selvedge is for

Selvedge has two audiences. Same tool, same pip install, same SQLite file under .selvedge/. Different scale of pain.

Teams running long-term, AI-coded codebases. When the project is big enough that you (or someone else) will touch it again in six months, twelve months, three years — but most of it was written by an agent whose context evaporated the day each PR shipped. git blame tells you what changed. Selvedge tells you why — even after the agent session, the prompt template, the developer who asked for it, and the model version are all long gone. This is the original use case: production codebases, schema decisions, migrations, dependency changes that need an audit trail that survives turnover.

Solo developers using Claude Code on everyday projects. Side projects, weekend builds, the small internal tool you keep poking at. You don't need enterprise governance — you just need to remember why you (or your agent) did the thing you did yesterday, last week, last sprint. Run selvedge init once. Add four lines to your CLAUDE.md. From then on, selvedge blame is muscle memory — a way to talk to your past self when your past self was an LLM.

If you've ever come back to your own AI-built project and thought "what was this for again?", Selvedge is the missing piece.

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The problem

Human-written code leaks intent everywhere — commit messages, PR descriptions, inline comments, the Slack thread that preceded it. AI-written code doesn't. The agent has perfect clarity about why it made each decision, but that context lives in the prompt and evaporates when the conversation ends.

Six months later, your team is debugging a schema decision with no trail. git blame tells you what changed and when. It can't tell you why.

Selvedge captures the why — live, by the agent itself, as the change is made. The diff is git's job. The why is Selvedge's.

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What's new in v0.3.4

The first-run release. The install funnel was six manual steps with three documentation lookups; v0.3.4 collapses it to one command. Drop-in upgrade for anyone on 0.3.3.

selvedge setup — interactive first-run wizard. Detects which AI tools are already on your machine (Claude Code, Cursor, Copilot) and walks through every install step in one pass: writes the MCP entry into each tool's config, drops the canonical agent-instructions block into your project's CLAUDE.md / .cursorrules / copilot-instructions file, runs selvedge init if needed, installs the post-commit hook. Every modified file gets a .bak next to it before any change reaches disk; re-running is a no-op. For CI bootstrap and devcontainer postCreateCommand: selvedge setup --non-interactive --yes.

selvedge prompt — canonical agent instructions on tap. Prints the recommended system-prompt block to stdout, or installs it idempotently into a target file with --install <file>. The block is sentinel-bracketed (<!-- selvedge:start --> / <!-- selvedge:end -->), so re-running --install updates the bracketed region without disturbing the rest of the file. No more copy-paste drift between releases.

selvedge watch — live tail of new events. Polls the SQLite store at --interval (default 1s) and prints each new event as it lands, Rich-formatted. Filters mirror selvedge history exactly: --since, --entity, --project, --agent. --json for piping into jq. Ctrl-C exits cleanly. Trust-but-verify surface for users who want to see what their agent is actually capturing in real time, and a much better debugging tool than running selvedge status repeatedly.

Better empty-state diagnosis in selvedge status and doctor. The "no events yet" message now distinguishes "MCP entry installed but agent hasn't reloaded" (5-minute restart-your-agent grace) from "MCP entry not installed anywhere we can see" (run selvedge setup). Surfaces the actual config path in either case so you know where to look.

See CHANGELOG.md for the full list including the test-coverage additions (54 new tests across test_setup.py, test_prompt.py, test_watch.py).

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What's new in v0.3.3

A discoverability + ergonomics release. No new MCP tools, no behavior changes that affect stored data — but the live tool schema is now substantially richer for the agents that call it and the directories that score it. Drop-in upgrade for anyone on 0.3.2.

Per-parameter descriptions on every tool. All 6 MCP tools now declare each parameter via Annotated[T, Field(description=...)], populating the per-parameter description field in tools/list. Previously each parameter shipped only type and title; the rich docstrings sat in the function body where agents couldn't see them at tool-call time. Coverage went 0/21 → 21/21. Agents picking which tool to call read these directly, so it's a DX win for Claude Code / Cursor use — not just a directory-score win.

MCP tool annotations. Each tool now declares readOnlyHint, destructiveHint, idempotentHint, openWorldHint, and a human-friendly title. log_change is the only writer (append-only, not idempotent — each call mints a new event). The five readers (diff, blame, history, changeset, search) are read-only and idempotent. None are open-world. Lets MCP clients gate or surface the tools appropriately.

Output schemas on every tool. New LogChangeResult and BlameResult TypedDicts give the JSON-RPC layer concrete output schemas to advertise — was missing on the two dict-returning tools. The list-returning ones already had auto-generated schemas, so all 6 are now consistent.

Custom server icon. A "stitched timeline" mark — a horizontal running stitch where each visible stitch is a captured change event. Lives at assets/icon.svg and a 512×512 assets/icon.png, shipped in the Smithery bundle.

log_change and blame return stable shapes. log_change now always returns id, timestamp, status, error, and warnings keys (with empty values when not applicable) — easier to type-check without branching. blame does the same on miss: every event field is empty, error carries the "no history found" message. Same conventions as before, just consistent payloads.

CLAUDE.md ↔ docs/architecture.md split. CLAUDE.md is now a slim agent-instructions file (sources of truth, code conventions, version bump checklist). Architecture, data model, MCP tool reference, full CLI reference, and the phase plan all moved to docs/architecture.md.

See CHANGELOG.md for the full list and reasoning.

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How Selvedge compares

There's a fast-growing "git blame for AI agents" category. Here's where Selvedge fits — and where it deliberately doesn't.

	Reasoning source	Granularity	Mechanism	Grouping	Storage
Selvedge	Captured live, by the agent in the same context that produced the change	Entity — DB column, table, env var, dep, API route, function	MCP server — agent calls it as work happens	Changesets — named feature/task slugs across many entities	SQLite, zero deps
AgentDiff	Inferred post-hoc by Claude Haiku from the diff at session end	Line	Git pre/post-commit hook	None	JSONL on disk
Origin	Captured at commit time	Line	Git hook	None	Local
Git AI	Attribution metadata	Line	Git hook + Agent Trace alliance	None	Git notes
BlamePrompt	Prompt-only	Line	Git hook	None	Local

Why "captured live" matters. AgentDiff and Origin generate reasoning after the change is made, by feeding the diff back to a second LLM call. Selvedge's reasoning is the agent's own intent, written from the same context window that produced the change — no inference, no hallucinated explanations, and an empty reasoning field is itself a useful signal (the agent didn't have one).

Why "entity-level" matters. Most tools attribute lines. Selvedge attributes things you actually search for: users.email, env/STRIPE_SECRET_KEY, api/v1/checkout, deps/stripe. The first question after git blame is usually "what's the history of this column", not "what's the history of lines 40–48 of users.py".

Why "changesets" matter. A Stripe billing rollout touches the users table, two new env vars, three new API routes, one dependency, and four functions across the codebase. Tag every event with changeset:add-stripe-billing and you can pull the entire scope back later — even if the original PR was broken into eight smaller ones over a month.

Selvedge ↔ Agent Trace. Agent Trace (Cursor + Cognition AI, RFC Jan 2026, backed by Cloudflare, Vercel, Google Jules, Amp, OpenCode, and git-ai) is an emerging open standard for AI code attribution traces. Selvedge isn't a competitor to it — it's a compatible producer. The design for selvedge export --format agent-trace is at docs/agent-trace-interop.md. Agent Trace is the wire format. Selvedge is the live capture + query layer that emits it.

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Install

pip install selvedge

Quickstart

1. Initialize in your project

cd your-project
selvedge init

2. Add to your Claude Code config

~/.claude/config.json:

{
  "mcpServers": {
    "selvedge": {
      "command": "selvedge-server"
    }
  }
}

3. Tell your agent to use it

Add to your project's CLAUDE.md:

You have access to Selvedge for change tracking.
Call selvedge.log_change immediately after adding, modifying, or removing
any DB column, table, function, API endpoint, dependency, or env variable.
Set `reasoning` to the user's original request or the problem being solved.
Set `agent` to "claude-code".
Before modifying an entity, call selvedge.blame to understand its history.

4. Query your history

selvedge status                        # recent activity + missing-commit count
selvedge diff users                    # all changes to the users table
selvedge diff users.email              # changes to a specific column
selvedge blame payments.amount         # what changed last and why
selvedge history --since 30d           # last 30 days of changes
selvedge history --since 15m           # last 15 minutes ('m' = minutes)
selvedge changeset add-stripe-billing  # all events for a feature/task
selvedge search "stripe"               # full-text search
selvedge stats                         # log_change coverage report
selvedge install-hook                  # auto-link commits to events
selvedge import migrations/            # backfill from migration files
selvedge export --format csv           # dump history to CSV

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How it works

Selvedge runs as an MCP server. AI agents in tools like Claude Code call Selvedge's tools as they work — logging structured change events to a local SQLite database.

Each event records:

• What changed (entity path, change type, diff)
• When (timestamp)
• Who (agent, session ID)
• Why (reasoning — captured from the agent's context in the moment)
• Where (git commit, project)

The diff is git's job. The why is Selvedge's.

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Entity path conventions

users.email           DB column (table.column)
users                 DB table
src/auth.py::login    Function in a file (path::symbol)
src/auth.py           File
api/v1/users          API route
deps/stripe           Dependency
env/STRIPE_SECRET_KEY Environment variable

Prefix queries work everywhere: users returns users, users.email, users.created_at, and any other entity under the users. namespace.

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MCP tools

When connected as an MCP server, Selvedge exposes:

Tool	Description
log_change	Record a change event with entity, diff, and reasoning
diff	History for an entity or entity prefix
blame	Most recent change + context for an exact entity
history	Filtered history across all entities
changeset	All events grouped under a named feature/task slug
search	Full-text search across all events

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CLI reference

selvedge init [--path PATH]               Initialize in project
selvedge status                           Recent activity summary
selvedge diff ENTITY [--limit N]          Change history for entity
selvedge blame ENTITY                     Most recent change + context
selvedge history [--since SINCE]          Browse all history
              [--entity ENTITY]
              [--project PROJECT]
              [--changeset CS]
              [--summarize]
              [--limit N]
selvedge changeset [CHANGESET_ID]         Show events in a changeset
                  [--list]                or list all changesets
                  [--project NAME]
                  [--since SINCE]
selvedge search QUERY [--limit N]         Full-text search
selvedge stats [--since SINCE]            Tool call coverage report (per-tool, per-agent)
selvedge doctor [--json]                  Health check: DB path, schema, hook, MCP wiring
selvedge install-hook [--path PATH]       Install git post-commit hook
                     [--window MIN]       (default 60 minutes)
selvedge backfill-commit --hash HASH      Backfill git_commit on recent events
                        [--window MIN]    (default 60 minutes)
selvedge import PATH                      Import migration files (SQL / Alembic)
              [--format auto|sql|alembic]
              [--project NAME]
              [--dry-run]
selvedge export [--format json|csv]       Export history to JSON or CSV
              [--since SINCE]
              [--entity ENTITY]
              [--output FILE]
selvedge log ENTITY CHANGE_TYPE           Manually log a change
             [--diff TEXT]                CHANGE_TYPE: add, remove, modify,
             [--reasoning TEXT]           rename, retype, create, delete,
             [--agent NAME]               index_add, index_remove, migrate
             [--commit HASH]
             [--project NAME]
             [--changeset CS]

All read commands support --json for machine-readable output.

Relative time in --since:

• 15m → last 15 minutes (m = minutes)
• 24h → last 24 hours
• 7d → last 7 days
• 5mo → last 5 months (mo or mon = months)
• 1y → last year

Unparseable inputs (e.g. --since yesterday) exit with a clear error rather than silently returning empty results. ISO 8601 timestamps are also accepted and normalized to UTC.

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Configuration

Method	Format	Example
Env var	SELVEDGE_DB=/path/to/db	Per-session override
Project init	selvedge init	Creates .selvedge/selvedge.db in CWD
Global fallback	~/.selvedge/selvedge.db	Used if no project DB found

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Coverage checking

Wondering how often your agent actually calls log_change? Two ways to check:

# Quick summary in the terminal
selvedge stats

# Cross-reference against git commits
python scripts/coverage_check.py --since 30d

The coverage script compares your git log against Selvedge events and shows which commits have associated change events. Low coverage usually means the system prompt needs strengthening — see docs/fallbacks.md for guidance.

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Contributing

git clone https://github.com/masondelan/selvedge
cd selvedge
pip install -e ".[dev]"
pytest

See CLAUDE.md for architecture details and the phase roadmap.

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License

MIT — see LICENSE.