deja-vu is a local memory system that indexes coding-agent session histories and makes relevant past work available to other agents. It helps users share fixes and context across Claude Code, Codex, Cursor, Copilot CLI, and other coding agents without using a language model or embeddings. The catalogue contains hooks, commands, MCP components, skills, plugins, and instructions for connecting agents to that memory.
Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add vshulcz/deja-vu/plugin install deja-vuWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/hooks/vshulcz/deja-vu/post-tool-use-failure)<a href="https://agentmods.dev/hooks/vshulcz/deja-vu/post-tool-use-failure"><img src="https://agentmods.dev/badge/hooks/vshulcz/deja-vu/post-tool-use-failure/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/hooks/vshulcz/deja-vu/post-tool-use-failure"><img src="https://agentmods.dev/badge/hooks/vshulcz/deja-vu/post-tool-use-failure.svg" alt="Reviewed on agentmods" width="80" height="20"></a>Grade A, and why
PostToolUseFailure scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 14d ago.
A static scan of the commands this hook runs, not an audit. A hook is shell that executes on your machine at the event it names, which is why every command in it is printed with what was found.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
{
"PostToolUseFailure": [
{
"matcher": "Bash|PowerShell",
"hooks": [
{
"type": "command",
"command": "\"${CLAUDE_PLUGIN_ROOT}/hooks/deja.sh\" hook-tool-after",
"timeout": 10,
"statusMessage": "Checking what fixed this before…"
}
]
}
]
}What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 14d ago First seen · 15 lines scan A 1c8caaef3eee
PostToolUseFailure is a hook published in the GitHub repository vshulcz/deja-vu (1,220 stars, last pushed yesterday), licensed MIT. Its token cost is not measured: a hook is shell that never enters the context. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-10-03.
Other hooks, from other repositories
PreToolUse
Runs before the agent uses a tool, running signet hook notifications -H codex --hook PreToolUse --codex. From Signet-AI/signetai.
PostToolUse
Runs after a tool call finishes for Edit, Write, MultiEdit, Bash and mcp__.* tool calls, executing _run_hook.sh via bash (7 commands). From lemoncrow-lab/lemoncrow.
SessionStart
Runs when a session starts, executing _run_hook.sh via bash. From lemoncrow-lab/lemoncrow.
UserPromptSubmit
Runs when you submit a prompt, before the agent sees it, executing _run_hook.sh via bash. From lemoncrow-lab/lemoncrow.
AfterAgent
Runs on the AfterAgent event, running an inline shell check. From 777genius/infinity-context.
PostToolUse
Runs after a tool call finishes for Write and Edit tool calls, executing format_and_lint.sh. From supabase/supabase.