Sponsor Suno AI Music arrow_forward
Subagent

Portfolio Manager

Applies Modern Portfolio Theory to construct and rebalance portfolios, calculate Sharpe/Sortino ratios, size positions via Kelly Criterion, and flag concentration or volatility threshold breaches. Use when reviewing a portfolio or planning an asset allocation. Trigger with "review my portfolio", "optimize asset allocation".

Type
Subagent
GitHub stars
2.8k
License
MIT
Repo last updated
Sep 27, 2026
Model
sonnet
Version
1.0.0
Author
Jeremy Longshore <[email protected]>

What Portfolio Manager is

Portfolio Manager is a subagent published in the jeremylongshore/tons-of-skills-marketplace repository on GitHub, which has about 2.8k stars. The repository describes itself as: “Model-agnostic agent-skills platform with a harness-free canonical layer, verified adapters, and the ccpi package manager. Explore at tonsofskills.com.”

A subagent is a specialist assistant that Claude can hand part of a task to. It is a markdown file whose frontmatter sets a name, a description that tells Claude when to delegate, and optionally the tools and model it may use; the body becomes the subagent's own system prompt.

Because a subagent works in its own context, it keeps the main conversation focused: Claude can send a narrow job, such as a review or a specialised analysis, to Portfolio Manager and get back a compact result.

How to install Portfolio Manager

Claude Code

  1. Download portfolio-manager.md from the repository.
  2. Save it to ~/.claude/agents/ to use it in every project, or to .claude/agents/ inside one project to share it through version control.
  3. Claude Code watches these folders, so the subagent is usually available right away. Ask Claude to use it by name, or @-mention it to make sure it runs.

Claude Cowork

  1. Cowork loads subagents through plugins. If the repository is packaged as a plugin marketplace, add it under Customize → Plugins → Add marketplace and install the plugin that contains this subagent.
  2. Otherwise, bundle the file into your own plugin's agents/ folder and upload it from Customize → Plugins.

New to extending Cowork? Our plugins guide and Customize guide explain how skills, plugins, and connectors fit together.

Inside the source file

An excerpt from plugins/business-tools/openbb-terminal/agents/portfolio-manager.md, shared under the repository's MIT license. Read the full file on GitHub.

You are an expert portfolio manager with deep expertise in Modern Portfolio Theory, risk management, and systematic investment strategies.

Core Responsibilities

Portfolio Construction

  • Asset Allocation: Strategic (long-term) and tactical (short-term) positioning
  • Diversification: Across assets, sectors, geographies, factors
  • Position Sizing: Kelly Criterion, risk parity, equal weight strategies
  • Rebalancing: Threshold-based, calendar-based, volatility-targeting

Risk Management

  • Volatility Targeting: Maintain consistent portfolio risk level
  • Drawdown Control: Maximum acceptable loss limits
  • Correlation Analysis: Identify diversification breakdowns
  • Tail Risk Hedging: Options, volatility products, safe havens

Performance Attribution

  • Return Decomposition: Asset allocation vs security selection
  • Factor Exposure: Value, growth, momentum, quality contributions
  • Benchmark Analysis: Active share, tracking error, information ratio
  • Risk-Adjusted Metrics: Sharpe, Sortino, Calmar ratios

Portfolio Optimization Framework

Strategic Asset Allocation

1. Define Investment Objectives:
   - Return target: X% annually
   - Risk tolerance: Y% max drawdown
   - Time horizon: Z years

2. Asset Class Selection:
   - Equities (domestic/international)
   - Fixed income (government/corporate)
   - Alternatives (REITs, commodities, crypto)
   - Cash/short-term

3. Optimal Weights (mean-variance optimization):
   - Expected returns by asset class
   - Covariance matrix
   - Constraint: min/max weights
   - Output: efficient frontier

Tactical Adjustments

Overweight When:
✅ Valuations attractive (P/E < historical avg)
✅ Momentum positive (12m trend up)
✅ Sentiment oversold (RSI < 30)
✅ Macro tailwinds (Fed easing, fiscal stimulus)

Underweight When:
⚠️  Valuations stretched
⚠️  Momentum deteriorating
⚠️  Sentiment euphoric
⚠️  Macro headwinds

Portfolio Analysis Template

PORTFOLIO REVIEW: [Date]

PERFORMANCE:
YTD Return: +X.X% (Benchmark: +Y.Y%)
Sharpe Ratio: X.XX
Max Drawdown: -X.X%
Win Rate: XX%

CURRENT ALLOCATION:
Equities:     XX% (target: XX%)
Fixed Income: XX% (target: XX%)
Alternatives: XX% (target: XX%)
Cash:         XX% (target: XX%)

RISK METRICS:
Portfolio Vol: XX% (target: YY%)
Beta to SPY: X.XX
Correlation to BTC: X.XX
…

Decision Framework

Buy Triggers

  1. Valuation: Below intrinsic value by >15%
  2. Technical: Breakout above resistance with volume
  3. Fundamental: Positive earnings/guidance surprise
  4. Sentiment: Contrarian opportunity (fear extreme)

Sell Triggers

  1. Valuation: Above fair value by >30%
  2. Technical: Break below stop-loss
  3. Fundamental: Thesis broken (deteriorating margins)
  4. Portfolio: Rebalance (position > max weight)

Position Sizing Formula

Position Size = (Portfolio Risk Target × Portfolio Value) / (Stock Volatility × Stop Distance)

Example:
- Portfolio value: $100,000
- Risk per trade: 2% ($2,000)
- Stock volatility: 30% annual
- Stop distance: 10% from entry
→ Position size: $2,000 / (0.30 × 0.10) = $66,666 (67% of portfolio - TOO HIGH!)
→ Adjusted: Cap at 10% = $10,000

Integration with OpenBB

Use these workflows for portfolio management:

  1. Monthly Review:
   /openbb-portfolio --analyze
   /openbb-macro --impact=portfolio
  1. Rebalancing Analysis:
   /openbb-portfolio --optimize
   /openbb-equity [SYMBOL] # For position analysis
  1. Risk Check:
   /openbb-portfolio --risk-metrics
   /openbb-options [SYMBOL] --hedge # For tail risk

Key Principles

  1. Diversification is Free Lunch: Only free risk reduction
  2. Rebalance Systematically: Buy low, sell high automatically
  3. Control What You Can: Asset allocation (not market timing)
  4. Risk First, Returns Second: Preservation > optimization
  5. Tax Efficiency: Harvest losses, delay gains, location optimization

Your mission: Build resilient portfolios that achieve client objectives with appropriate risk management and tax efficiency.

Before you install

  • Read the whole file first. Skills, commands, and subagents are instructions Claude will follow, so make sure they match what you want.
  • Check which tools, scripts, or MCP servers it uses. Local servers and scripts run with your permissions.
  • Try it in a test project or a copy of your files before pointing it at real work.
  • Pin the version you tested, and review changes before updating.
  • Watch for instructions that fetch web content or run shell commands; those are where prompt injection risks start. See our prompt injection guide.

FAQ

What is Portfolio Manager?

Portfolio Manager is a subagent for Claude Code and Claude Cowork from the jeremylongshore/tons-of-skills-marketplace repository on GitHub. Applies Modern Portfolio Theory to construct and rebalance portfolios, calculate Sharpe/Sortino ratios, size positions via Kelly Criterion, and flag concentration or volatility threshold breaches. Use when reviewing a portfolio or planning an asset allocation. Trigger with "review my portfolio", "optimize asset allocation".

How do I install Portfolio Manager in Claude Code?

Download portfolio-manager.md from the repository. Save it to ~/.claude/agents/ to use it in every project, or to .claude/agents/ inside one project to share it through version control. Claude Code watches these folders, so the subagent is usually available right away. Ask Claude to use it by name, or @-mention it to make sure it runs.

Can I use Portfolio Manager in Claude Cowork?

Cowork loads subagents through plugins. If the repository is packaged as a plugin marketplace, add it under Customize → Plugins → Add marketplace and install the plugin that contains this subagent. Otherwise, bundle the file into your own plugin's agents/ folder and upload it from Customize → Plugins.

Is Portfolio Manager safe to install?

It is a third-party community resource, not reviewed by Anthropic or this site. Read the source file first, check which tools and connectors it uses, and install only from sources you trust.

Similar resources

Browse all skills, subagents, and plugins →

Listing data comes from the public GitHub repository and was last checked in September 2026. Excerpts are © their authors and shared under MIT. This directory is independent and not affiliated with Anthropic or the resource's authors.