MCP server for Chart Library — visual chart pattern search engine. Find similar historical stock charts and see what happened next.
Chart Library MCP Server
Works with: Claude Desktop | Claude Code | ChatGPT | GitHub Copilot | Cursor | VS Code | Any MCP client
Cohort intelligence engine for stock chart patterns — give your AI agent the cohort of historical analogs, the full forward-return distribution, and the features that separated winners from losers. Calibrated, methodology-honest, no overstated confidence.
📖 What is cohort intelligence? · 🛠️ Full MCP setup guide · 🤖 Build an AI trading agent with Claude
25M+ pattern embeddings. 10 years of history. 19K+ stocks. One tool call.
> "What does NVDA's chart on 2024-08-05 1h look like historically?"
NVDA · 2024-08-05 · 1h — cohort of 500 historical analogs (485 with realized 5-day returns)
Distribution at 5 days forward: median: −1.3% p10 ·· p90: −11.3% ·· +6.8% (80% empirical band) win rate: 44% cohort_score: 0.31 (modest)
Features that separated winners from losers: + creditspreadstate = tight + macro_state = bullish + pctoff52w_low (further off) − vol_regime = low
Summary: NVDA's 1-hour pattern on 2024-08-05 has 500 historical analogs. The cohort's 5-day distribution is bearish-leaning (median −1.3%, win rate 44%) — the historical record does NOT show this pattern typically resolving bullish. Conditioning on tight credit spreads and a bullish macro state would have separated the outperformers within the cohort.
A retrieval, not a forecast. No hallucinated predictions. No cherry-picking. Just the empirical record your agent can cite.
Quick Start
pip install chartlibrary-mcp
Claude Desktop (One-Click Install)
Download the chart-library-6.1.0.mcpb extension file and open it with Claude Desktop for automatic installation.Claude Code
claude mcp add chart-library -- chartlibrary-mcp
Claude Desktop (Manual)
Add toclaudedesktopconfig.json:
{
"mcpServers": {
"chart-library": {
"command": "chartlibrary-mcp",
"env": {
"CHARTLIBRARYAPIKEY": "clyour_key"
}
}
}
}
Cursor / VS Code
Add to.cursor/mcp.json or VS Code MCP settings:
{
"servers": {
"chart-library": {
"command": "chartlibrary-mcp",
"env": {
"CHARTLIBRARYAPIKEY": "clyour_key"
}
}
}
}
GitHub Copilot (VS Code)
Add to.vscode/mcp.json in your project (this file is already included in the chart-library repos):
{
"servers": {
"chart-library": {
"command": "chartlibrary-mcp",
"env": {
"CHARTLIBRARYAPIKEY": "clyour_key"
}
}
}
}
Copilot Chat will auto-detect the MCP server when you open the project. Use @mcp in Copilot Chat to invoke tools.
ChatGPT (Developer Mode)
ChatGPT connects to MCP servers via remote HTTP endpoints. To set up:- Enable Developer Mode: Go to ChatGPT Settings > Apps > Advanced settings > Developer mode (requires Pro, Plus, Business, Enterprise, or Education plan)
- Create a connector: In Settings > Connectors, click Create and enter:
https://chartlibrary.io/mcp
- Authentication: No Authentication (or OAuth if using an API key)
- Use in conversations: Select "Developer mode" from the Plus menu, choose the Chart Library app, and ask questions like "What does NVDA's chart look like historically?"
Note: The remote endpoint athttps://chartlibrary.io/mcpuses Streamable HTTP transport. If you need SSE fallback, usehttps://chartlibrary.io/mcp/sse.
Remote MCP Endpoint
For any MCP client that supports remote HTTP connections:https://chartlibrary.io/mcp
This endpoint supports both Streamable HTTP and SSE transports, no local installation required.
Free tier: 200 calls/day, no credit card required. Get an API key at chartlibrary.io/developers or use basic search without one.
What Can Your Agent Do With This?
"Should I be worried about my TSLA position?"
> search(query="TSLA") → cohort_id
> explain(cohortid=..., style="positionguidance")
Signal: HOLD Of the historical analogs to this setup, those that exited early avoided a drawdown 3/10 of the time; those that held gained a further +2.1% median over the next 5 days. No exit signal triggered — the cohort's record leans toward continuation, not reversal.
"What sectors are rotating in right now?"
> context(target="market")
Sector relative strength (30-day): Leaders: XLK Technology +4.2% · XLY Cons. Disc. +3.1% · XLC Comm. +2.8% Laggards: XLU Utilities −1.4% · XLP Cons. Staples −2.1% · XLRE Real Estate −3.3%
Regime: Risk-On (growth > defensives), SPY above 20d, VIX mid-band.
"How does AMD behave when the broad tape is weak?"
> search(query="AMD 2024-06-18") → cohort_id
> cohortgroupby(cohortid=..., by="ctxspytrend_20d")
AMD's cohort, split by the SPY trend at each analog's date: SPY weak (bottom quartile): median 5d −5.2% · p10/p90 −11.4%/+1.1% · 18% positive SPY strong (top quartile): median 5d +2.6% · p10/p90 −3.1%/+8.4% · 61% positive
A distribution conditioned on the tape — historical analogs, not a beta forecast.
14 Canonical Tools
Chart Library v6 exposes the same granular surface as the remote server at chartlibrary.io/mcp — so the pip package, the Claude connector, and the REST API all use the same tool names. The core loop is search → pullcomps → cohortintrospect. Chain tools via the compsetid / cohort_id handle for sub-second refinement without re-running kNN.
| Tool | What it does | |------|-------------| | search | Entry point. Find similar historical patterns for an anchor; returns a comp-set handle you can chain. mode= supports text (default), live_bars (raw OHLCV), similar (cohort-level neighbors). | | pullcomps | The flagship. Pull the comp set for a subject (symbol, date, timeframe) — the historical analogs, what they did next, the drivers that separated the best outcomes, and our coveragerecord. Front-of-house lexicon: subject · compsetid · compcount · compstrength · matchquality · drivers · uprate · conditions (calm / normal / stressed). Same engine as cohort_analyze with the new vocabulary applied at the boundary. | | cohortanalyze | Same engine as pullcomps under the original field names (cohortid, featureimportance, winrate, volregime, …). Kept callable verbatim for existing integrations; new ones should prefer pull_comps. | | cohort_introspect | Slice/probe a stored comp set by ANY attribute (macro · technical · event) and get per-subset stats vs the full-cohort baseline. No kNN re-run. "Of the 300 analogs, how do the post-earnings-week ones do?" | | cohort_attribution | Within-cohort winner/loser attribution — which member traits separated the forward-return tail from the rest, each with a by-date cluster-bootstrap CI and a false-discovery decision. Descriptive, never causal. | | track_record | Historical predicted-vs-realized coverage of our calibrated bands (a track record, not a forecast). The nominal 80% band held 80.8% across 302,880 prior cases. | | symbol_intelligence | Layer 5 memory — per-symbol feature reliability + achieved calibration across prior analyses. Ground a read in whether a feature has historically been reliable for this ticker. | | analyze | Analytic metrics. metric= accepts anomaly, volumeprofile, crowding, correlationshift, earningsreaction, patterndegradation, regime_accuracy, decompose (slice winners vs losers), clusters (cohort-internal grouping). | | context | Situational data. target= accepts "market", a ticker symbol ("NVDA"), {"symbol": ..., "date": ...} for lightweight anchor metadata, or "system" for DB coverage. | | explain | Narrative + rankings derived from a cohort. style= accepts filterranking (which filter shifts the distribution most), prose (plain-English summary), positionguidance (exit signals), risk_ranking. | | portfolio | Multi-holding weighted conditional distribution. Runs per-holding cohorts in parallel, weight-averages the distributions, ranks tail contributors. | | report_feedback | File an error or improvement suggestion back to the project. |
Full-cohort handover — hand the raw cohort back so you can bucket/sort by your objective, not our default lens:
| Tool | What it does | |------|-------------| | cohort_members | The full cohort, one record per analog, with rich per-member metadata (forward outcomes, regime, anchor fundamentals, news, chart events). Slice and bucket it yourself. | | cohortgroupby | Partition the cohort by one dimension (volregime, sectoretf, momentum5d, …) → per-bucket outcome distributions vs baseline. The one-call "does this dimension matter?" primitive. | | cohortrerank | Reorder the cohort by a weighted composite of member fields you name (e.g. "ret5d:1,distance:-0.5") — impose your objective on the analogs, fully auditable. |
These tools replace hallucinated "on average this pattern returns X%" with real conditional base rates. The full distinction — what they do and how to read responses — is documented at /concepts/cohort-intelligence and /concepts/reading-a-cohort-response.
Typical agent flow
1. search(query="NVDA 2024-06-18") → compsetid
- pull_comps(symbol="NVDA", date="2024-06-18",
filters={"vol_regime": ["high"]})
→ comp set: distribution + drivers
- cohortintrospect(cohortid=...,
where={"events.dayssinceearnings": {"max": 5}})
→ how the post-earnings subset did
- cohortgroupby(cohortid=..., by="sector_etf") → outcome split by sector
Migrating from v5 (umbrella) / v4 / v3
v6 converges on the granular naming the live remote/connector surface already used. The v5 umbrella tools — cohort (depth=), discover (mode=), narrative (mode=), and decisionbrief — are now deprecated but still callable, so existing code keeps working. cohort(depth="full") forwards to cohortanalyze. New agents should reach for the canonical tools above.
| v5 umbrella call (deprecated) | v6 canonical | |--------|-------------| | cohort(depth="full", ...) | cohort_analyze(...) | | cohort(depth="basic", cohortid=...) then slice | cohortintrospect(cohort_id=..., where={...}) | | cohort(depth="compare", comparewith={...}) | cohortcompare(...) (still callable) | | portfolio(mode="symbolintel", symbol=...) | symbolintelligence(symbol=...) | | discover(mode="picks" | "dailysetups") | discoverpicks(...) / /api/v1/agent/setups | | narrative(mode="pulse" | "alerts") | narrativepulse(...) / narrativealerts(...) (still callable) |
The v4-era granular aliases (cohortcompare, decompose, clusters, livesearch, similarcohorts, anchorfetch, narrativepulse, narrativealerts, discoverpicks, getdaily_setups) remain deprecated-but-callable and forward to the canonical surface.
The v3-era tools (searchcharts, getcohortdistribution, analyzepattern, etc.) were removed in v5. If your code still calls them, pin chartlibrary-mcp<5.0.0 until you migrate. The mapping:
| Legacy (removed in v5) | Replacement | |--------|-------------| | searchcharts, searchbatch, getdiscoverpicks | search | | getcohortdistribution, refinecohortwithfilters, runscenario, getregimewinrates, comparetopeers | cohortanalyze (+ cohort_introspect to refine) | | detectanomaly, getvolumeprofile, getcrowding, getearningsreaction, getcorrelationshift, getpatterndegradation, getregimeaccuracy | analyze (metric=) | | getsectorrotation, getstatus, getmarket_context | context | | getpatternsummary, explaincohortfilters, getexitsignal, getriskadjusted_picks | explain (style=) | | getportfoliohealth | portfolio | | analyzepattern, getfollowthrough, checkticker | search + cohort_analyze |
How It Works
Chart Library indexes a large library of historical chart patterns and exposes them behind a conditional-distribution API. Every query returns sample sizes, percentiles, and calibrated forward-return bands — never a point forecast.
When your agent calls search("NVDA") and chains cohort_analyze, the server:
- Resolves NVDA's current chart state to a stored embedding
- Retrieves the cohort of historically similar patterns
- Looks up what happened over the following 1, 3, 5, and 10 days
- Returns the calibrated distribution + a plain-English summary via Claude Haiku
API Key
| Tier | Calls/day | Price | |------|-----------|-------| | Sandbox | 200 | Free | | Builder | 5,000 | $29/mo | | Scale | 50,000 | $99/mo |
Get your key at chartlibrary.io/developers.
export CHARTLIBRARYAPIKEY=clyour_key
Links
Privacy Policy
Chart Library's privacy policy is published at chartlibrary.io/privacy and covers:
- What we collect: account info (email when you create an account), usage data (search queries, features used), and device information (browser, OS, IP). API queries are stored for service operation and analytics.
- How we use it: providing and improving the service, processing your searches, communicating about your account, and analyzing usage patterns.
- Data sharing: we do not sell personal data. Operational service providers (hosting, analytics, payment processing) receive only what's necessary to provide the service.
- Third-party services: queries may be processed by upstream providers (Polygon.io for market data, Anthropic for narrative summaries) under their own privacy policies.
- Retention: account info while your account is active; usage data is anonymized or deleted periodically. You can request deletion at any time.
- Security: encryption in transit and at rest. No method of transmission is 100% secure.
- California rights (CCPA): right to know, right to delete, right to opt-out, non-discrimination.
- Contact: support@chartlibrary.io for any privacy inquiry.
chartlibrary.io (no local file or directory contents, no clipboard, no browser history). Your CHARTLIBRARYAPI_KEY is sent only as a Bearer header to authenticate with the chart-library API.
Security
- Transport: all calls to the remote API are HTTPS (TLS 1.2+).
- Authentication: optional API key passed as a Bearer header; the free Sandbox tier requires no key.
- No write access to your environment, files, or other accounts. The single MCP tool that performs a write (
report_feedback) only writes back to chart-library's own feedback inbox and never touches your system.
License
MIT. See LICENSE.
Chart Library provides historical pattern data for informational purposes. Not financial advice.