MCP Connector

Index and recall coding decisions across all AI agents

deja indexes coding-agent session history already on disk into one shared, redacted memory layer any agent can recall from.

Works with claudecodexcursorcopilotaider

89
Spark score
out of 100
Updated 9 days ago
Source checked Sep 10, 2026
Version 0.19.5
Models
claudegemini 2 0qwen 2 5

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Why it matters

Give every coding agent on your machine shared memory by indexing all their past sessions from disk, so any agent can recall solutions, decisions, and working commands from conversations that happened months ago in different tools-without manual search or starting from scratch.

Outcomes

What it gets done

01

Index gigabytes of agent session history retroactively with millisecond lookup performance

02

Surface relevant past decisions automatically before file edits or command execution

03

Retrieve working command invocations when the same error occurs again

04

Provide cross-agent recall via MCP so Claude remembers what you solved in Cursor

Source

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Capabilities

Tools your agent gets

recall

MCP tool that retrieves relevant memory from agent history to answer questions

remember

MCP tool that stores explicit facts and decisions in the notes source

Overview

Deja Vu

deja-vu (deja) indexes the session history already written to disk by 25+ coding agents into one shared, redacted local memory layer, recalling automatically at session start, before risky actions, and after failed commands via an MCP recall tool, with lifecycle tracking for rejected decisions and cross-machine sync. Use it whenever an agent might re-solve something already settled in a prior session, in the same agent or a different one - it works from the binary alone, with MCP wiring and auto-recall as an optional install step.

What it does

deja indexes the session history that Claude Code, Codex, Cursor, and roughly twenty-two other coding agents already write to local disk, turning it into one shared memory layer any of them can read - starting full from day one rather than empty, since it indexes everything already on disk including sessions from before deja was installed. Its MCP recall tool answers "we fixed this three weeks ago" in whichever agent asks, regardless of which agent originally solved it, and recall arrives automatically at session start, on every prompt, before a file is edited or a command runs, and after a command fails - nobody has to search for it. It indexes the actual work, not just the conversation: which files each turn opened, which commands ran and their exit status, and the exact text spans an edit replaced, the parts a session summary throws away. Measured over 43 real compactions, a session summary keeps 77% of decisions and 0.2% of the commands that were run; deja hands back the other 99.8%. Published benchmarks: 85.3% hit@1 on LongMemEval-S, 69.6% on LoCoMo, both harnesses shipped in the repo and runnable on public datasets; on a real store of 1,551 sessions and 143k messages across 5.2GB and nine harnesses, a lookup runs about 0.4ms median in-process and an end-to-end query about 0.2s, with an index that's incrementally updated so only a changed session file gets re-read, sized at about 160MB, roughly 3% of the corpus.

When to use - and when NOT to

Use it whenever an agent is about to re-solve, re-debug, or re-explain something already settled in a prior session, in the same agent or a different one - it's meant to make cross-agent recall automatic rather than something the user has to remember to ask for. It stores a decision's lifecycle explicitly rather than deleting anything: marking a decision rejected records that it was tried and reverted, with the reason, and every later hit for that session shows it, while an accepted mark reverses that. A hit also reports when the ground has shifted, such as files touched this session having changed since, and stays silent rather than claiming something is unchanged when it can't tell. Semantic, embedding-based recall is optional: pointing deja embed at a local Ollama, LM Studio, or OpenAI-compatible endpoint via DEJA_EMBED_URL lets rephrased queries still hit, but lexical search and MCP recall work unchanged with no embedding runtime configured at all - a remote embedding endpoint receives only redacted, truncated indexed text, never raw source files, and OPENAI_API_KEY is only ever sent automatically to api.openai.com, never to a local or third-party endpoint.

Capabilities

The MCP server exposes one tool, deja, parameterized by a mode of recall, context, blame, fix, how, or remember (six older individual tool names still work for anything already wired to them). The CLI covers retroactive natural-language search across all indexed history, deja blame <path> for which sessions discussed a file and why, deja files <topic> for the reverse lookup, deja how <tool> for the actual invocation this machine has run before, deja fix <error> for what ran after that same error last time, and deja friction for errors that hit three or more separate sessions. Credentials are redacted at index time - AWS keys, api_key=/token= assignments, bearer tokens, raw JWTs, PEM blocks, provider tokens, credential-bearing URLs, and high-entropy unknown-shape values all become a redacted placeholder while the surrounding text stays searchable; sharing and export commands reapply that redaction on the way out. A forget command removes a session and writes a tombstone so a later reindex can't silently restore it, with an unforget option to lift it, and a config file holds one project-exclusion pattern per line. A sync command moves memory between machines append-only with no cloud in between, and a handoff command packages live context to continue work in a different agent. Twenty-five harnesses are supported in total, with matrix-documented per-harness support for MCP recall, auto-recall, a loadable skill, a CLI command, session resume, and handoff. deja stats --card draws a year of agent activity as a terminal heatmap, and can write it to an SVG file for a profile README or convert it to a PNG on the project's own web page; deja view renders the whole indexed history as one local, server-free HTML page.

How to install

curl -fsSL https://raw.githubusercontent.com/vshulcz/deja-vu/main/install.sh | sh
deja install --auto

The second command wires MCP recall into every detected agent, turns on session-start auto-recall where supported, and builds the first index. Alternative installs: brew install deja-vu, go install github.com/vshulcz/deja-vu/cmd/deja@latest, npx @vshulcz/deja-vu "query" to try without installing, scoop install deja-vu on Windows since the shell installer itself exits with an unsupported-OS error there, or each supported harness's own plugin marketplace. Indexing, search, and redaction all work from the binary alone with nothing wired in; the doctor command correctly reports every MCP target as not wired in that configuration, which is expected. Networking is used only for updates, machine-to-machine sync, and a version check - indexing and search stay entirely local otherwise.

Who it's for

Anyone running more than one coding agent, or the same agent across many project sessions, who is tired of re-explaining or re-debugging something already solved months earlier - especially useful for switching agents mid-project, recovering context after a crash or a session-history cleanup, or auditing what an agent actually did, such as files touched, commands run, and exit codes, rather than what a session summary claims it did. MIT licensed.

Source README

deja-vu

The one memory your coding agents share, built from the history already on your disk.

Your agent is about to re-debug something you fixed in March - in a different agent. deja indexes the sessions Claude Code, Codex, Cursor and every other agent on this machine already wrote to disk, and hands the right one back in whichever agent asks.

The same question put to the same agent twice: without memory it has no record of it, with deja it answers with the decision from eight months earlier

Nobody searched anything - the agent called deja itself. Every line is quoted from two real sessions.

Every memory tool starts empty and records forward. deja starts full.

And nobody has to ask for it: recall arrives at session start, on every prompt, before a file is edited or a command runs, and after one fails. Keys and tokens are stripped as the index is built, so what reaches the model is safe to send.

85.3% hit@1 on LongMemEval-S · 69.6% on LoCoMo · millisecond lookups over 5 GB of history
Both harnesses ship in this repo and run on the public datasets in minutes · check the numbers yourself

CI Release MCP Toplist MIT License

English | 中文

Docs · Benchmarks · How it compares

Install

curl -fsSL https://raw.githubusercontent.com/vshulcz/deja-vu/main/install.sh | sh
deja install --auto

What deja prints after the first index: the mark, the agents it found, and a query taken from your own history

Ten seconds to install, about ten to index, and it is useful. The second command wires MCP
recall into every agent it finds, turns on session-start recall where the agent supports
it, and builds the first index so the next session does not pay for it.

Start a new agent session and ask it something you worked on months ago:

have we dealt with jwt refresh rotation before? check your memory

It does not have to be asked, either - with auto-recall the agent already knows what you
solved in that project when the session opens.

Other ways to install, and what to do if you want less than all of it

brew install deja-vu, go install github.com/vshulcz/deja-vu/cmd/deja@latest,
or npx @vshulcz/deja-vu "query" to try it without installing anything. Desktop apps that
take MCP servers as bundles can open the .mcpb from the
latest release; it carries the binary.

Claude Code, Codex, Cursor, Qwen, OpenClaw and Copilot can take the same plugin bundle from
their own marketplaces instead:

claude plugin marketplace add vshulcz/deja-vu && claude plugin install deja-vu@deja-vu

On Windows the install script exits with unsupported OS - it is a shell script. Use
Scoop instead, from the main bucket every Scoop install already has:

scoop install deja-vu

Or take deja-vu_<version>_windows_amd64.zip from the
latest release and put deja.exe on
your PATH, e.g. in %USERPROFILE%\.local\bin.

The binary alone is a complete install for searching: index, search, show, ctx, blame,
--json and redaction need nothing else. deja install is what wires MCP into your agents
and turns on session-start recall - worth having, and optional. On a binary-only setup
deja doctor reports every MCP target as not-wired, which is that setup working as
intended. deja warmup also leaves a skill at ~/.agents/skills/deja-search/SKILL.md
that teaches an agent the CLI contract - deja search --json, ctx, blame, how to read
tier and total - so it knows history is searchable without MCP. The copy in the repo is
skills/deja-search/SKILL.md.

deja install --all is --auto without the session-start recall: agents answer from memory
when they decide to call it, rather than starting each session with it. The
agent setup guide covers what each
harness supports, aider's read-only context file, and the Windows cmd /c deja mcp wrapper.

What gets written into each agent's own guidance file

Install also writes user-level guidance for the harnesses it detects: Claude Code, Codex, opencode, Gemini CLI, Antigravity, Qwen, Kimi Code, pi, Copilot, VS Code Copilot Chat, Cursor, Goose, OpenClaw, Hermes, Roo Code, omp, Amp, prime-agent, DeepSeek Harness, Continue, Crush and Zed each get it in their own guidance file (or under the configured XDG_CONFIG_HOME). Re-run rewrites deja's skill or marked block without changing surrounding user content. Use deja install --all --no-guidance to opt out; Grok Build gets the shared skill in ~/.agents/skills, which is what it reads; the ~/.grok/GROK.md written beside it is for the unrelated community CLI that shares that directory. Cursor has no user-level instructions file, so it gets the shared skill in ~/.agents/skills - one of the four places Cursor reads skills from - read only when something looks relevant rather than every session.

What you get

Solve it in Codex. Claude remembers. Twenty-five coding agents write every conversation
to local files, and deja turns those files into one memory layer all of them read.

Retroactive search deja "connection pool exhausted" over gigabytes, including everything from before you installed deja. Natural-language questions fall back to a relevance tier. Time is a hint, not a filter.
Cross-agent recall The MCP recall tool answers "we fixed this three weeks ago" in whichever agent asks, whoever solved it originally.
It survives compaction Measured over 43 compactions: the summary keeps 77% of the decisions and 0.2% of the commands you ran. deja hands back the other 99.8%.
Recall at the point of action Before an agent edits a file or runs a command, deja names that file's prior decision or that command's working invocation, from a PreToolUse hook. When a command fails, a PostToolUse hook answers with what followed that same error here before - the pair an agent never thinks to ask for.
It indexes the work, not just the talk The files each turn opened, the commands that ran with their exit status, and the exact spans an edit replaced. That is the part every summary throws away.
Four more: rejected decisions, staleness, sync and handoff, redaction
It knows what held deja promote <id> --state rejected --note "why" marks a decision you reverted. Every later hit for that session shows it was tried and rejected, with the reason. Nothing is deleted, and --state accepted takes the mark back.
It says when the ground moved A hit reports 4 files this session touched have changed since, and says nothing when it cannot tell. It never claims anything is unchanged.
Sync and handoff deja sync ssh laptop moves memory between machines, append-only, no cloud in the middle. deja handoff --to codex packages the live context so you can continue in another agent.
Redaction Keys, tokens, JWTs and private key blocks are stripped at index time, so the cache is safe to keep.

Your own work, wrapped

deja stats --card draws it in the terminal; give it a filename and it writes an
SVG for a profile README. To post it anywhere else, turn it into a
PNG
- that page converts it in your own
browser.

deja stats card: a year of agent sessions as a heatmap, the agents they came from, and the longest one

The full feature reference lives in the docs.

CLI

$ deja "jwt refresh token"
[claude] api        · Jul 8 · 8f31c0a9 — 2 matches
  login started failing after refresh token rotation; jwt kid mismatch in tests
  fixed by reloading jwks cache after rotateKey and adding a clock-skew test
[codex]  web        · Jul 1 · b77d91e2 — 1 match
  refresh token cookie needed SameSite=Lax in local callback flow

Ask your history

Command What it does
deja <query> Search every history. Multi-word is AND and quoted phrases require contiguous text; a query with no exact match then tries word forms and close spellings, which is where a substring reaches its word (code finds opencode).
deja With an index and a terminal: today's sessions, recalls served, a question you asked in more than one session, and a wall your agents keep hitting.
deja blame <path> Which sessions discussed a file, what was decided, and why.
deja files <topic> The other direction: which files the work on a subject actually touched.
deja how <tool> How this machine actually runs a thing, with the real flags, from what agents ran before.
deja fix <error> What this machine ran after that same error before, when the error did not come back.
deja friction Errors that hit three or more separate sessions, with the harnesses named.
Using what it finds, and moving it between machines

Use what it finds

Command What it does
deja ctx <query> Markdown digest of the best match, ready to pipe into a prompt.
deja resume <id> Reopen a found session in its native harness.
deja restore <path> Hand back a span an agent replaced, from the old_string its edit recorded. Never writes over the original.
deja promote <id> Distill a session into a curated note with provenance, tags and a lifecycle state. Notes outrank raw transcripts.
deja share <id> A sanitized session digest for a colleague, with secrets already scrubbed.

Move it and check it

Command What it does
deja sync export/import/ssh Move memory between machines. Watermarked, append-only, idempotent.
deja view Your whole memory as one local HTML file. No server, nothing leaves the machine.
deja stats Your agent work, wrapped. --card draws it in the terminal, --card <file>.svg writes one for a profile, --html a browsable timeline.
deja doctor [--deep] Self-diagnosis, and with --deep, proof of the index against the sources.
deja mcp The stdio MCP server, which is what deja install wires in.

Full reference: commands and
JSON output.

MCP tools

The server exposes one tool, deja, with a mode. deja install wires it in, so
this is only needed to configure an agent by hand. The six older tool names
(recall, recall_context, blame, fix, how, remember) still answer for
anything already wired to them.

Arguments and return shapes
Tool Arguments Returns
deja mode, plus query, path, error, what, text, tags?, harness?, project?, since?, limit?, offset?, all? Depends on the mode, below.
Mode Arguments it reads Returns
recall query, harness?, limit?, offset? Dense matching snippets, capped at 4KB.
context query, harness? Markdown digest of the best-matching session.
blame path, harness?, project?, since?, limit?, all? Sessions that discussed a file.
fix error, project?, limit? What this machine ran, or changed, after that same error before.
how what, project?, limit? The real invocation, from what agents ran here.
remember text, project?, tags? Stores a durable decision for later recall.

Supported harnesses

aider · Amp · Antigravity · Claude Code · Cline · Codex CLI · Copilot CLI · VS Code Copilot Chat · Cursor · DeepSeek Harness · Gemini CLI · Goose · Grok Build · Hermes · Kimi Code · omp (Oh My Pi) · OpenClaw · opencode · Continue · Crush · pi · prime-agent (PrimeIntellect) · Qwen Code · Roo Code · Zed.

What each one supports
Harness MCP recall Auto-recall Skill Command Resume Handoff Needs
aider deja aider
Amp -
Antigravity -
Claude Code -
Cline -
Codex CLI -
Copilot CLI -
VS Code Copilot Chat - paste -
Cursor sqlite3 (IDE chats)
DeepSeek Harness paste zstd
Gemini CLI -
Goose deja goose
Grok Build sqlite3 (grok-dev store)
Hermes paste sqlite3
Kimi Code -
omp (Oh My Pi) -
OpenClaw paste -
opencode sqlite3
Continue - paste -
Crush sqlite3
pi -
prime-agent (PrimeIntellect) -
Qwen Code -
Roo Code paste roo CLI (editor tasks reopen in the editor)
Zed paste sqlite3 + zstd

✅ works · - possible, not built yet · ✕ the harness has no such mechanism · ⚠ blocked by an upstream bug · ? not investigated

Custom store locations go through DEJA_*_ROOT variables, and each agent's own relocation
variable is honored too. The
session format registry documents
the observed paths, record schemas and role mapping per harness, with synthetic fixtures
keeping those descriptions checked against the parsers.

Harnesses with a package of their own

deja install --auto wires all six of these like every other harness, and
that stays the shortest path. They also have a package in their own ecosystem,
for people who install extensions there rather than from a CLI:

Harness Package Install
opencode npm opencode-deja opencode plugin opencode-deja
DeepSeek Harness npm dsh-deja dsh plugin --profile web add dsh-deja
Zed deja-context-server Zed → Extensions → deja
Kimi Code plugin deja /plugins install https://github.com/vshulcz/deja-vu
Codex CLI plugin deja-vu codex plugin marketplace add https://github.com/vshulcz/deja-vu then codex plugin add deja-vu@deja-vu
Grok Build plugin deja grok plugin marketplace add xai-org/plugin-marketplace then grok plugin install deja

Either path is enough on its own, and having both is not a problem: the
opencode, dsh, Kimi, Grok and Codex packages read what deja install wrote and
contribute only what is missing, and in Zed both halves use one server id, so
there is nothing to have twice whichever order you install in.

Each uses the deja you already have; the copy it bundles is only the fallback.

The same search is also a skill, for any agent that loads a SKILL.md:

npx skills add https://github.com/vshulcz/deja-vu --skill deja-search   # skills CLI: Claude Code, Cursor, Goose, Copilot…
openclaw skills install @vshulcz/deja-search                            # ClawHub
hermes skills install vshulcz/deja-vu/skills/deja-search                # Hermes

The skill drives the deja binary from the install step above; it does not bundle one.

Semantic recall (optional)

Point deja embed at a local Ollama, LM Studio or OpenAI-compatible endpoint with
DEJA_EMBED_URL and rephrased queries still hit. Without a reachable runtime, lexical
search and MCP recall continue unchanged. OpenAI Platform works with its standard key:

export OPENAI_API_KEY='sk-...'
export DEJA_EMBED_URL='https://api.openai.com/v1/embeddings'
export DEJA_EMBED_MODEL='text-embedding-3-small'
deja embed

With no DEJA_EMBED_URL set, deja probes localhost:11434 and localhost:1234,
so a machine already running Ollama or LM Studio is picked up without being asked.
DEJA_EMBED_OFF=1, or DEJA_EMBED_URL=off, turns that probe off - any other
configured DEJA_EMBED_URL still wins.

For another authenticated OpenAI-compatible endpoint, set DEJA_EMBED_KEY explicitly:

export DEJA_EMBED_URL='https://example.com/v1/embeddings'
export DEJA_EMBED_MODEL='embedding-model'
export DEJA_EMBED_KEY='...'
deja embed

DEJA_EMBED_KEY takes precedence. OPENAI_API_KEY is used automatically only for an
HTTPS api.openai.com URL; it is never implicitly sent to local or third-party endpoints.

Where the vectors live and what they cost

The sidecar sits beside the index as .vectors.bin, not inside index.db. Float32 vectors
cost roughly 4 MB per 1k messages for a 1,024 dimension model. A remote endpoint receives
the redacted indexed text, truncated to about 2k characters, but never raw source files.
With Ollama or LM Studio, embedding stays local and needs no key.

Proof

deja bench recall     # ranking regression floor, CI fails if recall drops
deja bench context    # 30 seeded task chains plus five negative controls
deja bench block      # does the answer survive into what deja hands over

bench block asks the question the other three cannot: with the right session in
hand, does the block carry what that session settled. Eight sessions discuss each
subject and one of them settles it, in the middle of its own transcript rather
than at the end - so the baseline arm, the newest turns of the top hit, scores
zero and an arm above zero had to choose.

Arm Carries the answer Median tokens
deja-block (session-start block) 1.00 665
deja-digest (context digest) 1.00 1656
newest-turn (baseline) 0.00 289
cold 0.00 0

The context experiment compares deja-recall against full-history, naive grep and cold
context. With the default seed:

Arm Median tokens Median coverage Negative-control tokens
deja-recall 286 1.00 0
full-history 16,919 1.00 14,920
naive-grep 57,489 1.00 0
cold 0 0.00 0

Same fact coverage as grepping the raw logs for about 200x fewer tokens, and about 60x
fewer than replaying the matched sessions in full, while injecting nothing on the chains
where no prior fact is relevant. The corpus generator and the relevance labels are
ordinary reviewed Go. Audit what "relevant" means before trusting any figure, ours
included.

Measured on a real store of 1,551 sessions and 143k messages - 5.2 GB across nine
harnesses:

Measurement Result
Lookup, in process ~0.4 ms median (deja bench recall), ~25 ms on the LongMemEval-S haystacks
deja <query>, end to end ~0.2 s median on that store: process start, the freshness check over every store, ranking, printing
Freshness check alone ~30 ms when nothing changed
Index size 160 MB, ~3% of corpus

The index is incremental. When a session file grows, only that file is re-read.

How it works

Local inverted index in ~/.cache/deja: parse the JSONL and SQLite stores, redact
credentials, write records.bin plus token buckets, and track per-file state in
manifest.gob so repeat runs only ingest what changed. The MCP server, stats, share and
sync all read that one index. Details in docs/ARCHITECTURE.md.

FAQ

Does anything leave my machine? No, unless you ask it to. See the
data flows.

What about secrets already in my logs? They stay in the original harness files, which
are your agent's data. Known shapes - AWS keys, api_key=/token= assignments, bearer
tokens and bare JWTs, PEM blocks, provider tokens, high-entropy values - are stripped as
the index is built, so they do not reach digests, shares or sync exports. Pattern matching
is not secret detection: a shape it does not know can pass through. See the
security model.

Will it slow my agent down? A recall is a lexical lookup against a local index:
~0.4 ms median, and nothing waits on a model. A hook adds the process start and a
freshness check over your stores on top of that - tens of milliseconds on a store of
a few gigabytes.

Do I have to change how I work? No. The agent calls recall itself, and with
auto-recall it already knows the project's prior decisions when the session opens.

How is this different from the other memory tools?

deja Memory platforms
(Mem0, Letta, memU)
Session search
(cass)
Knows work from before you installed it yes no yes
Capture step none, the transcripts are the memory the agent or your code writes facts none
Needs an LLM or embedding key no yes optional
Recalls without being asked at session start and before a tool runs no no

engram is the strongest of the
record-forward tools and worth your time if that model fits you; it still starts empty and
knows only what an agent chose to save. The
full comparison covers eleven of them.

Where is Claude Code session history stored, and can I search it? Under
~/.claude/projects, one JSONL file per session; Codex keeps ~/.codex/sessions, Cursor a
SQLite state.vscdb. deja search reads them all in place, deja last lists the recent
sessions of every agent, and deja view opens the whole history as one local page. Paths
for each agent: where sessions are stored.

My Claude Code session history disappeared. Is it gone? Claude Code deletes transcripts
older than 30 days (cleanupPeriodDays in ~/.claude/settings.json), and claude --resume lists
only what is left. A session deja indexed before the cleanup stays searchable after the
file is gone. Details: session files on disk.

What about Windows? Builds exist and CI runs the suite there. macOS and Linux are the
battle-tested paths. Field reports welcome in #9.

How do I wipe everything?

deja uninstall --all
rm -rf ~/.cache/deja

Guides

Written for the situation rather than the feature:

Per harness: opencode · DeepSeek Harness · Kimi Code · Zed · Grok Build · Gemini CLI · Qwen Code · OpenClaw · Goose · Cline · pi and omp · Hermes

Try it on your own history

curl -fsSL https://raw.githubusercontent.com/vshulcz/deja-vu/main/install.sh | sh
deja install --auto

Ten seconds to install, about ten to index. The next session your agent opens, it
already knows what you solved in that project - including everything from before
you installed this.

FAQ

Common questions

Discussion

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