vshulcz/deja-vu
This server exposes one deja tool for searching and using the user's local AI coding session history across 35+ agents.
recall — search past sessions by exact error string, name, path, or natural language.
context — retrieve the full story/digest of a specific session when a recall hit is not enough.
blame — understand why a file is the way it is from past sessions before editing or deleting it.
fix — after hitting an error, see what this machine ran after that same error before.
how — find the real command and flags the user runs for a tool, instead of guessing.
orient — see commands past sessions ran in this project and the files they worked in.
remember — store one settled decision for a later session.
Optional filters:
harness(which agent),project, andlimit.Results may include bracketed markers for the user's own later judgement; when helpful, open your reply with
déjà vu: <what> — <how you used it> (deja:<session id>).
curl -fsSL https://raw.githubusercontent.com/vshulcz/deja-vu/main/install.sh | sh
deja install --autoHighlights
Starts full. Months of history from before you installed it are searchable on day one:
deja "connection pool exhausted"over gigabytes.One memory, every agent. A fix found in Codex comes back in Claude Code, Cursor or opencode; all thirty-five agents read the same index.
Nobody has to ask. Recall arrives at session start, before a file is edited or a command runs, and after a command fails.
Survives compaction. Over 43 measured compactions the summary kept 77% of the decisions and 0.2% of the commands; deja hands back the rest (how).
Indexes the work, not just the talk. The files each turn opened, the commands with their exit status, the exact spans an edit replaced.
Knows what held.
deja promote <id> --state rejectedmarks a reverted decision, and every later hit says it was tried and why it was dropped;--state acceptedtakes the mark back.Says when the ground moved. A hit reports 4 files this session touched have changed since, and stays quiet when it cannot tell.
Local and private. No model, no embeddings, no server. Keys and tokens are stripped as the index is built (privacy).
Moves with you.
deja sync ssh laptopbetween machines, no cloud in between;deja handoff --to codexto continue in another agent.One Go binary. macOS, Linux and Windows, through Homebrew, Scoop, winget, npm or
go install.
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.
The full feature reference lives in the docs.
Related MCP server: ctx-memory
Install
The two commands at the top are the whole install on macOS and Linux:
curl -fsSL https://raw.githubusercontent.com/vshulcz/deja-vu/main/install.sh | sh
deja install --autoTen 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.
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, Cursor, Qwen and OpenClaw can take the same plugin bundle from
their own marketplaces instead (Codex has a bundle of its own, in the table under
Harnesses with a package of their own).
Copilot CLI installs it too but takes only the skill, so use deja install copilot-auto there:
claude plugin marketplace add vshulcz/deja-vu && claude plugin install deja-vu@deja-vuOn Windows the install script exits with unsupported OS — it is a shell script. Use
Scoop, from the main bucket every Scoop install already has, or winget, which ships with Windows:
scoop install deja-vu
winget install vshulcz.deja-vuOr 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.
Install also writes user-level guidance for the harnesses it detects: Claude Code, Codex, opencode, Gemini CLI, Antigravity, Qwen, Kimi Code, pi, Senpi, 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. Kilo Code, gajae-code, Command Code, Cherry Studio and Reasonix get the skill, and Kiro a steering file, from their own install target.
Privacy
Indexing and search are local. The network is used only by deja update, deja sync ssh,
the version check in deja doctor, and deja embed against an endpoint you configure.
Credentials are stripped as the index is built: cloud and provider keys, tokens and JWTs,
PEM blocks, passwords in URLs or stated in prose. Each becomes [redacted:<kind>] and the
text around it stays searchable. The source transcripts still hold them
(one machine had 84 in 42 sessions):
deja secrets names those sessions without printing a value, and deja secrets --scrub
rewrites the ones it can, keeping the original beside the file.
deja forget drops sessions and keeps them dropped across rebuilds. ~/.config/deja/exclude
skips a project per line, or a whole store with harness:opencode. The
security model has the data flows and what redaction cannot catch.
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 flowAsk your history
Command | What it does |
| 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 ( |
| 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. |
| What the last session in this directory was doing: the task, what it settled, the files in flight, the last command and whether it failed — derived from the transcript, not from a note someone remembered to write. |
| Which sessions discussed a file, what was decided, and why. With a line: the commit that last changed it, and the session that wrote that line or the text the commit replaced. |
| The other direction: which files the work on a subject actually touched. |
| How this machine actually runs a thing, with the real flags, from what agents ran before. |
| What this machine ran after that same error before, when the error did not come back. Never a merge, a force push or a deletion. |
| Errors that hit three or more separate sessions, with the harnesses named. |
Use what it finds
Command | What it does |
| Markdown digest of the best match, ready to pipe into a prompt. |
| Reopen a found session in its native harness. |
| Hand back a span an agent replaced, from the |
| Distill a session into a curated note with provenance, tags and a lifecycle state. Notes outrank raw transcripts. |
| A sanitized session digest for a colleague, with secrets already scrubbed. |
Move it and check it
Command | What it does |
| Move memory between machines. Watermarked, append-only, idempotent. |
| Your whole memory as one local HTML file. No server, and the file never leaves the machine. |
| Your agent work, wrapped. |
| Which sessions' source transcripts carry credentials, and what kind. Never prints a value. |
| Keep your standing rules in |
| The turns where you corrected an agent, across every tool, numbered with their session. Ask your agent to suggest rules and it groups them; nothing is written until you pick. |
| Self-diagnosis, and with |
| The stdio MCP server, which is what |
Full reference: commands and JSON output.
MCP tools
The server exposes one tool, deja, with a mode; deja install wires it in. One tool
costs 477 tokens of definitions a turn, against 8,283 for the largest of the seven servers
measured in day zero. The six
older tool names (recall, recall_context, blame, fix, how, remember) still answer.
Tool | Arguments | Returns |
|
| Depends on the mode, below. |
q carries whatever the mode asks about. The per-mode names below are still
accepted; they are no longer declared, because the schema is read every turn
whether or not the tool is called.
Mode |
| Also reads | Returns |
| the question, or an exact error string, name or flag |
| Dense matching snippets, capped at 4KB. |
| the same as recall |
| Markdown digest of the best-matching session. |
| a file path |
| Sessions that discussed a file. |
| the failing output, verbatim |
| What this machine ran, or changed, after that same error before. |
| the tool or target, e.g. |
| The real invocation, from what agents ran here. |
| nothing — it asks about the project |
| The commands past sessions ran here and the files they worked in. |
| one durable fact or decision |
| 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 · Cherry Studio · Senpi · gajae-code · Kimchi Coding · Command Code · ZCode · Kiro · Kilo Code · Roo Code · Zed · CodeWhale · Reasonix.
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, CLI tool output) |
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 | sqlite3 (2026.8+ store); zstd for .zst archives |
opencode | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | sqlite3 |
Continue | ✅ | ⚠ | ✅ | ✅ | ✅ | paste | — |
Crush | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | sqlite3 |
pi | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | — |
prime-agent (PrimeIntellect) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | — |
Qwen Code | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | — |
Cherry Studio | ✅ | ✕ | ✅ | ✕ | ✕ | paste | import the server once in Settings -> MCP; enable the skill for the agent |
Senpi | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | none |
gajae-code | ✅ | ✅ | ✅ | ✅ | ✅ | paste | none |
Kimchi Coding | ✅ | ⚠ | ⚠ | ⚠ | ✅ | paste | none |
Command Code | ✅ | ✅ | ✅ | ✅ | ✅ | paste | none |
ZCode | ✅ | ✅ | ? | ? | ✅ | paste | sqlite3 for the CLI database |
Kiro | ✅ | ⚠ | ✕ | ? | ✅ | paste | sqlite3 for the CLI database |
Kilo Code | ✅ | ⚠ | ✅ | ✅ | ✅ | paste | sqlite3 for the CLI store |
Roo Code | ✅ | ⚠ | ✅ | ✅ | ✅ | paste | roo CLI (editor tasks reopen in the editor) |
Zed | ✅ | ✕ | ✅ | ✅ | ✕ | paste | sqlite3 + zstd |
CodeWhale | — | — | ? | ? | ✅ | paste | none |
Reasonix | ✅ | ✅ | ✅ | ✅ | ✅ | paste | zstd for 1.x sessions |
✅ works · — possible, not built yet · ✕ the harness has no such mechanism · ⚠ waiting on the harness itself · ? 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 every one 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 |
|
DeepSeek Harness | npm |
|
Zed |
| Zed → Extensions → deja |
Kimi Code | plugin |
|
Codex CLI | plugin |
|
Grok Build | plugin |
|
OpenClaw | ClawHub and npm |
|
pi (and omp) | npm |
|
Hermes | memory provider |
|
Either path works alone, and both together double nothing: each package reads what
deja install already wrote and uses the deja you already have.
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 # HermesThe 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 embedWith 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 embedDEJA_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.
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
Millisecond lookups, and on LongMemEval-S 88.1% hit@1 (470-question cleaned set) and 87.4% hit@1 on all 500 questions; on LoCoMo retrieval, 70.5% hit@1. On a task this machine had already solved, 58% fewer tokens: eleven runs an arm, 53,558 against 126,222 with nothing wired, and 52,815 against 103,443 on a later build with the arms alternated. Both retrieval harnesses ship in this repo and run on the public datasets in minutes: benchmarks · what one task costs.
The rest is measured by deja bench:
deja bench recall # ranking floor: 100 queries, half Russian, 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
deja bench prompt # what the per-prompt hook fires on, and what it fires on wrongly
deja bench ingest # what an update costs: unchanged, a turn, a new transcript, a rename, a rewrite
deja bench read # what it costs to read a database-backed store, and what one long value does to itbench block asks the question the others 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 |
| 1.00 | 665 |
| 1.00 | 1656 |
| 0.00 | 289 |
| 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 | 1,096 | 1.00 | 0 |
full-history | 80,547 | 1.00 | 78,145 |
naive-grep | 273,238 | 1.00 | 0 |
cold | 0 | 0.00 | 0 |
Same fact coverage as grepping the raw logs for about 250x fewer tokens, and about 70x 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 2,419 sessions and 179k messages, 1.9 GB of transcripts:
Measurement | Result |
Lookup, in process | 0.7–0.8 ms median ( |
| ~0.2 s median on that store: process start, the freshness check over every store, ranking, printing |
Freshness check alone | ~50 ms when nothing changed |
Index size | 200 MB, ~10% of corpus |
The same store has since grown to 2,754 sessions, 358k messages and 5.7 GB. A cold full build over it takes 71 s and writes a 232 MB index — 4% of the corpus, because the share falls as transcripts repeat themselves — and the end-to-end median is unchanged at 0.25 s.
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
No, unless you ask it to. See the data flows.
They stay in the original harness files, which
are your agent's data; deja secrets names the sessions that carry them so you can rotate
and delete, and --scrub rewrites the transcripts it can reach. 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.
A recall is a lexical lookup against a local index: 0.7–0.8 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.
No. The agent calls recall itself, and with auto-recall it already knows the project's prior decisions when the session opens.
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 15 of them.
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.
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.
Builds exist and CI runs the suite there. macOS and Linux are the battle-tested paths. Field reports welcome in #9.
deja uninstall --all
rm -rf ~/.cache/dejaGuides
Written for the situation rather than the feature:
Does your agent remember previous conversations? — what each agent keeps between sessions, and what it drops
Session files on disk — how big
~/.claude/projectsgets, and what deleting it costsThe agent lost the context you had — after a crash, a clear, or a session that came back empty
The context window is full — what compaction keeps, measured, and what to do instead
Resuming yesterday's session — find it across every agent, reopen it in the one that owns it
Why agents forget between sessions · Where each agent keeps its history
What compaction drops · Switching agents · Auditing an agent · Exporting a conversation · Across machines · What memory costs
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 --autoTen 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.
Contributing
make build test lint, then CONTRIBUTING.md. Adding a harness starts in
the parser registry. Priorities and non-goals are in
ROADMAP.md. Good first issues are labeled.
Support
Bugs and questions go to issues. Anything you think is exploitable goes through the private advisory link in SECURITY.md instead. What deja reads, what it never sends anywhere, and how to exclude a project or forget a session is under Privacy.
License
MIT © Vladislav Shulcz
Available Tools
1 tooldejaA
This user's own past sessions from every AI coding tool on this machine — not general knowledge, not library docs. Modes:
recall: search past sessions. An exact error string, name or path is the strongest query; your own words work too.
context: the full story of one session, when a recall hit is not enough.
blame: why a file is the way it is, before you edit or delete it. Sessions, not git authorship.
fix: you just hit an error — what this machine ran after that same error. Pass the output verbatim.
how: the command and flags this user really runs for a thing, instead of a guessed one.
orient: the commands past sessions ran in this project and the files they worked in, before you go reading.
remember: store one settled decision for a later session. A bracketed marker on a result is the user's own later judgement; act on what it says. When a result helps, open your reply with one line: "déjà vu: — (deja:)". Say nothing about recalls that did not help.
| Name | Required | Description | Default |
|---|---|---|---|
| q | No | What to ask about: the question or exact token; for blame a path, for fix the failing output verbatim, for remember the fact. | |
| mode | Yes | ||
| limit | No | Max results. | |
| harness | No | Optional filter, the agent that wrote it: claude, codex, opencode, aider and 31 more (`deja sources`). | |
| project | No | Optional project filter; for remember, where it is filed. |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations only declare openWorldHint=false; the description adds real behavioral context beyond that — that bracketed markers encode the user's own later judgement, that fix should receive output verbatim, and that a successful hit requires an opening acknowledgement line in a specific format. These are non-obvious protocol behaviors an agent could not infer from structured fields.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The mode list is front-loaded and each line is a single clause that earns its place; the purpose statement comes first. Slightly dense and conversational in the closing sentences, but there is no dead weight.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a 5-parameter, mode-driven tool with no output schema and no siblings, the description covers the mode semantics, the input expectations, and the response acknowledgement convention well. It stops short of describing the general shape of a result beyond the bracketed-marker note, which is the only remaining gap.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 80%, so the baseline is 3, but the description adds genuine meaning to the `mode` enum by defining what each value actually asks for. It also ties `q` to mode-specific expectations (a path for blame, verbatim output for fix), reinforcing rather than just restating the schema.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Opens with a specific, scoped statement of what the resource is ('This user's own past sessions from every AI coding tool on this machine') and explicitly negates the confusable alternatives ('not general knowledge, not library docs'). The mode list then names seven distinct operations, so an agent knows exactly what each invocation returns without opening the schema.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Every mode carries its own when-to-use condition: blame is 'before you edit or delete it', fix is 'you just hit an error', orient is 'before you go reading'. It also states when *not* to speak ('Say nothing about recalls that did not help'), which is unusually explicit routing guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
1 tool update
v0.21.5- Changed
deja1 field changed- changed
Input schema / properties / harness / descriptionPrevious value: -"Optional filter, the agent that wrote it: claude, codex, opencode, aider and 30 more (`deja sources`)."New value: +"Optional filter, the agent that wrote it: claude, codex, opencode, aider and 31 more (`deja sources`)."
1 tool update
v0.21.1- Changed
deja14 fields changed- removed
Input schema / properties / allRemoved value: -{ - "description": "blame: every project, not just this one.", - "type": "boolean" -} - removed
Input schema / properties / errorRemoved value: -{ - "description": "fix: the failing output, verbatim. Multi-line pastes are fine.", - "type": "string" -} - changed
Input schema / properties / harness / descriptionPrevious value: -"Optional filter, the agent that wrote the session: claude, codex, opencode, aider and 30 more — `deja sources` lists them."New value: +"Optional filter, the agent that wrote it: claude, codex, opencode, aider and 30 more (`deja sources`)." - removed
Input schema / properties / mode / descriptionRemoved value: -"Which capability to use." - changed
Input schema / properties / mode / enumPrevious value: -[ - "recall", - "context", - "blame", - "fix", - "how", - "remember" -]New value: +[ + "recall", + "context", + "blame", + "fix", + "how", + "orient", + "remember" +] - removed
Input schema / properties / offsetRemoved value: -{ - "description": "recall: skip this many ranked matches, to page without re-ranking.", - "type": "number" -} - removed
Input schema / properties / pathRemoved value: -{ - "description": "blame: absolute, relative, or bare filename.", - "type": "string" -} - changed
Input schema / properties / project / descriptionPrevious value: -"Optional project filter; for remember, where the note is filed (default notes)."New value: +"Optional project filter; for remember, where it is filed." - added
Input schema / properties / qAdded value: +{ + "description": "What to ask about: the question or exact token; for blame a path, for fix the failing output verbatim, for remember the fact.", + "type": "string" +} - removed
Input schema / properties / queryRemoved value: -{ - "description": "recall and context: an exact token — error string, function name, flag — or the question in your own words.", - "type": "string" -} - removed
Input schema / properties / sinceRemoved value: -{ - "description": "blame: age such as 30d or 24h.", - "type": "string" -} - removed
Input schema / properties / tagsRemoved value: -{ - "description": "remember: optional navigation tags, searchable as #tag.", - "items": { - "type": "string" - }, - "type": "array" -} - removed
Input schema / properties / textRemoved value: -{ - "description": "remember: one durable fact, decision or conclusion.", - "type": "string" -} - removed
Input schema / properties / whatRemoved value: -{ - "description": "how: tool or target, e.g. 'go test', 'docker compose', a script name.", - "type": "string" -}
1 tool update
v0.21.0- Changed
deja1 field changed- changed
Input schema / properties / harness / descriptionPrevious value: -"Optional filter, the agent that wrote the session: claude, codex, opencode, aider and 29 more — `deja sources` lists them."New value: +"Optional filter, the agent that wrote the session: claude, codex, opencode, aider and 30 more — `deja sources` lists them."
1 tool update
v0.20.2- Changed
deja1 field changed- changed
Input schema / properties / harness / descriptionPrevious value: -"Optional filter, the agent that wrote the session: claude, codex, opencode, aider and 21 more — `deja sources` lists them."New value: +"Optional filter, the agent that wrote the session: claude, codex, opencode, aider and 29 more — `deja sources` lists them."
1 tool update
v0.19.5- Changed
deja1 field changed- changed
Input schema / properties / harness / descriptionPrevious value: -"Optional filter: claude, codex, opencode, aider, gemini, cursor, antigravity, grok or qwen."New value: +"Optional filter, the agent that wrote the session: claude, codex, opencode, aider and 21 more — `deja sources` lists them."
7 tool updates
v0.19.3- Removed
blame - Added
deja - Removed
fix - Removed
how - Removed
recall - Removed
recall_context - Removed
remember
1 tool update
v0.19.1- Changed
recall1 field changed- changed
Input schema / properties / query / descriptionPrevious value: -"Search terms; specific tokens (error strings, function names, flags) match best. Multiple words are ANDed."New value: +"An exact token — error string, function name, flag — matches strongest. Failing that, the question in your own words; several words are tried together first and then ranked, so a phrase still finds things."
2 tool updates
v0.17.0- Added
fix - Added
how
1 tool update
v0.16.9- Changed
remember1 field changed- added
Input schema / properties / tagsAdded value: +{ + "description": "Optional navigation tags, searchable as #tag.", + "items": { + "type": "string" + }, + "type": "array" +}
TDQS
Scored across 1 tool
The seven modes of the single 'deja' tool are described reasonably well, but several overlap conceptually: recall/context/blame/orient are all 'find a past session,' and fix/how/orient all answer 'what command was run.' An agent must choose a mode argument rather than a tool, which adds friction but the descriptions do steer selection.
With only one tool there is no cross-tool convention to violate, and the mode names (recall, context, blame, fix, how, orient, remember) are all consistent lowercase single-word verbs/nouns. There is simply too little surface to demonstrate a strong naming pattern.
A single tool is far too thin for a surface that hides seven distinct operations behind a mode parameter. The modes would be better expressed as separate tools so an agent can match intent to a named capability instead of guessing a mode string.
Retrieval, error-fix lookup, blame, orientation, and one write path (remember) cover the core memory workflows, but there is no way to list, update, or forget stored memories, and no session enumeration, leaving lifecycle gaps.
Maintenance
Related MCP Connectors
Hosted MCP memory: save sessions/decisions once, search from Claude, Cursor, ChatGPT. EU-hosted FTS.
Shared memory for coding agents. Stop re-explaining your codebase every session.
Persistent cross-session memory shared by Codex, Claude Code, ChatGPT, and other AI agents.
- SeturosOAuthcom.seturos
Shared work memory for Claude Code, Codex, Cursor and chat, scoped to each repository.
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