google/mantis-history
>- Analyzes the repository's version control system (VCS) history to extract past vulnerabilities, security fixes, and vulnerability patterns. Use as an initial pre-processing step to build a historical vulnerabilities database (workspace/historical_learnings.jsonl) that informs subsequent stages about past issues and fixes. Don't use for code reviews, writing test scripts, or patching code.
npx skills add https://github.com/google/mantis --skill mantis-history
Historical Vulnerability Extractor. Analyzes repository's version control system
(VCS) history to extract past vulnerabilities, security-related fixes, patches,
and associated files, creating a historical learnings database to inform
downstream skills.
/mantis-historyextract past vulnerabilities and fixes, producing a structured historical
learnings file (workspace/historical_learnings.jsonl).
--snapshot_root/--snapshot_id/--state_root. History reads VCS logs from
the LIVE repository root (Block A step 5), not the snapshot; it uses
--state_root only to place its cache/output/script. All absent -> DEGRADED
(behaves as today, live cwd).
workspace/.mantis_state.json (to track current loop pass).mantis-summary.md (optional, if available).workspace/historical_learnings.jsonl.--state_root/workspace/ (cache, historical_learnings.jsonl,extraction script): kept outside the target tree. Optional history_status
marker (UNSUPPORTED_VCS / PARTIAL_SHALLOW).
and is never truncated to empty while the cache is non-empty. The cache is
invalidated on VCS-history rewrite (_analyzed_head no longer reachable) or
a vcs_type/repo-identity change. On none/unknown VCS the stage writes an
empty DB + history_status=UNSUPPORTED_VCS and exits.
LOCATOR RESOLUTION (before reading ANY target code or artifact):
0. ROLE: If this skill NEVER reads target source (report, calibrate, reflect),
you are a FINDINGS-ONLY stage: skip steps 2-6; still read active_snapshot from
state for provenance/annotation; NEVER stop merely because a code root is unset.
1. Determine CODE_ROOT, in this priority order:
a. If --target_root is passed on THIS invocation, CODE_ROOT = --target_root.
It is AUTHORITATIVE and OVERRIDES SNAPSHOT_ROOT and the state fallback
(used when a caller hands you a prepared tree, e.g. a patched shadow).
b. Else if --snapshot_root (or SNAPSHOT_ROOT) is passed, use it.
c. Else read state_root/workspace/.mantis_state.json (state_root from
--state_root if passed, else ./workspace/... relative to the current dir)
-> active_snapshot.root / .snapshot_id / .snapshot_pinned.
d. Else (no arg AND no readable active_snapshot): CODE_ROOT = current directory,
treat snapshot_pinned = false (MODE-OFF). Do NOT stop.
2. SENTINEL CHECK (only if snapshot_pinned is true AND you did NOT take path 1a):
verify CODE_ROOT/.mantis_snapshot_id exists and equals SNAPSHOT_ID. If missing
or different -> STOP "snapshot sentinel mismatch". (A --target_root tree (1a) is
deliberately mutated and is sentinel-EXEMPT.)
3. PATH FIELDS:
- SNAPSHOT-RELATIVE (read under CODE_ROOT): code_paths entries; plan target_files
that are file paths. Strip ONLY a trailing ":<digits>". A code_paths entry
containing "://" is a URL/endpoint, NOT a file read. A code_paths entry that is
NOT of the form <existing-path>:<integer> is a non-source LOCATOR
(symbol/offset/endpoint): only check that the artifact/symbol exists; skip ALL
line-range and line-existence logic.
- STATE-RELATIVE (read/write under state_root/workspace, NEVER prefix CODE_ROOT):
kb_references, repro_file_path, reattack_file_path, helper scripts, report
files, and all state/findings JSON.
4. Never WRITE under CODE_ROOT when snapshot_pinned is true. Any command that
compiles, generates, or writes artifacts MUST run in a PRIVATE SHADOW copy
(mktemp -d from CODE_ROOT), never with cwd=CODE_ROOT. Read-only inspection may
cd into CODE_ROOT.
5. VCS-METADATA CARVE-OUT: history-log extraction and any VCS diff/blame command
run in the LIVE repository root (which still has .git/.hg/.repo), NOT CODE_ROOT
(the snapshot copy strips VCS metadata). Do NOT stop merely because CODE_ROOT
lacks .git/.hg/.repo.
6. Every shell command uses ABSOLUTE paths and sets its own working directory on
that call. Do NOT assume the working directory persists between calls.
CRITICAL for history: the pinned snapshot copy STRIPS .git/.hg/.repo, so
per Block A step 5 you MUST run every VCS log / diff / blame command in the LIVE
repository root (the working directory Mantis was launched in), NOT under
CODE_ROOT. Do NOT stop because CODE_ROOT lacks VCS metadata. Write the cache,
workspace/historical_learnings.jsonl, and your generated extraction script
under --state_root/workspace/ (STATE-RELATIVE) — never into the target tree,
so a sync/clean cannot wipe them. Record active_snapshot.snapshot_id on
entries only for provenance.
Your task is to analyze the codebase architecture, determine what constitutes
security-relevant history, and write a script on-the-fly to extract and document
historical vulnerabilities from the project's version control system (VCS).
Execute the history analysis stage as follows:
mantis-summary.md if available) or quicklyinspect the root codebase structure to understand the primary files,
programming languages, and core components.
corruption, authentication bypass, SQL injection, buffer overflow, or
others) are relevant to this project and what keywords or commits should be
targeted.
vcs_type from .mantis_state.json vcs_info (or detect it in the LIVE
root). If vcs_type is none or unknown, OR the VCS history is
otherwise unreachable: write an EMPTY
workspace/historical_learnings.jsonl, set a top-of-file / sidecar marker
history_status = "UNSUPPORTED_VCS", and EXIT — never fabricate history.
For multi-vcs (.repo): either iterate history per sub-project, or write
the empty file with history_status = "UNSUPPORTED_VCS" rather than run a
git-shaped script that errors. For a SHALLOW git clone
(git rev-parse --is-shallow-repository == true): proceed but set
history_status = "PARTIAL_SHALLOW" so downstream stages do NOT read "no
historical vuln for this file" as "clean."
workspace/.mantis_state.json and resolve the current ISO 8601 timestamp.
workspace that interacts with your repository version control system (VCS)
history logs.
remains cost-effective and runs efficiently, the script must implement the
following optimizations:
the script should dynamically determine relevant keywords for commit
message screening. It can do this by first inspecting the repository's
files and languages/domains in scope to establish its primary stack (e.g.
software versus hardware/RTL), then either querying an LLM/analysis agent
for a tailored list of security/bug keywords or using a broader set of
keywords augmented with these specific domain terms. Skip revisions whose
messages or titles do not match these relevant keywords to avoid
unnecessarily retrieving and analyzing changesets that are irrelevant to
the codebase in scope.
non-production code (e.g., tests, documentation, or configuration files).
Skip commits with excessively large diffs (e.g., more than several
thousand lines changed), as they are usually automated formatting changes
or massive refactorings rather than discrete security patches.
cache (JSON or SQLite) under workspace/ mapping
revision_id -> analyzed, AND storing the full extracted record for each
analyzed revision plus an _analyzed_head high-water mark and the
vcs_type + repo identity the cache was built against. On each run,
REBUILD workspace/historical_learnings.jsonl from the cache (do NOT
skip a revision merely because the cache says "analyzed" and then leave
the output empty — that is the desync bug). NEVER truncate a non-empty
output DB to empty. Only analyze revisions NEWER than _analyzed_head.
Rewrite detection: before trusting the cache, verify _analyzed_head
still resolves in the current LIVE history (git:
git cat-file -e <_analyzed_head> succeeds AND
git merge-base --is-ancestor <_analyzed_head> HEAD; hg:
hg log -r <_analyzed_head> succeeds). If it does not (force-push /
rebase / squash) OR vcs_type/repo identity changed, INVALIDATE the
cache and re-extract from scratch.
commit diff, the script should batch multiple commit diffs and messages
(e.g. 3 to 5 commits) into a single LLM call. Ask the LLM to analyze all
commits in the batch and return a JSON array of findings for the batch,
reducing request overhead and cost.
initial commit analysis/filtering, and only fall back to heavier model
tiers if deeper verification of a suspected vulnerability is needed.
security-relevant, the script should retrieve the commit diffs and
messages/change descriptions.
subagent messages or Agent API subcommands) or use an LLM subagent to
analyze the changes' diffs and messages to determine whether a
revision/commit was a security fix, what component was affected, the
vulnerability type, impact, and the mitigation diff. Make sure it uses
batching and caching to minimize API calls.
keywords. Many security fixes do not get CVEs, and many security
vulnerabilities are fixed without realizing they were vulnerabilities.
into a JSONL file named workspace/historical_learnings.jsonl, matching
the following format:
workspace/historical_learnings.jsonl){
"revision_id": "...",
"title": "...",
"description": "...",
"code_paths": ["file:line_number"],
"vuln_type": "...",
"mitigation_diff": "...",
"cve": "...",
"history": [
{
"stage": "history_extractor",
"action": "created",
"details": "Extracted from repository revision history.",
"pass_number": <current_pass_number>,
"timestamp": "<current_iso8601_timestamp>"
}
]
}
revisions, and generate the workspace/historical_learnings.jsonl file.
workspace/historical_learnings.jsonl has been written successfully and
contains extracted data.
When complete, notify the user.
Take google/mantis-history from the repository into ~/.claude/skills for personal
use, or into .claude/skills inside a project.
The agent identifies a skill by the name field in its header. Two skills with the
same name cannot sit side by side — one of them will be ignored.