Scheduled SEC Analysis with Claude Code

Claude Code can run scheduled tasks using cron skills, combining the OMNI Datastream API with AI-powered analysis on a recurring cadence. In this tutorial you will set up a weekly 13F portfolio comparison report that runs every Friday evening and summarizes how major funds changed their positions.

Prerequisites

An Omni Datastream API key (set as OMNI_DATASTREAM_API_KEY)
Claude Code installed and authenticated
Familiarity with Custom Skills (recommended)
(Optional) Familiarity with the Monitor 13F Holdings tutorial

What you will build

A scheduled Claude Code skill that:

Runs every Friday at 6:00 PM
Fetches the latest 13F filings for a list of funds
Compares current holdings to previous quarter
Generates a summary of new positions, exits, and significant changes
Saves the report as a Markdown file

Step 1 --- Create the analysis skill

Create a skill file that defines the 13F comparison workflow. Save it as .claude/skills/weekly-13f-review.md in your project:

---
name: weekly-13f-review
description: >
  Compare 13F holdings for major funds between the current and previous quarter.
  Identify new positions, exits, and significant weight changes.
---

# Weekly 13F Portfolio Review

## Endpoints Used
- GET /v1/ownership/13f?cik={cik}&date={date}

## Fund Watchlist
- Berkshire Hathaway (CIK: 0001067983)
- Bridgewater Associates (CIK: 0001350694)
- Renaissance Technologies (CIK: 0001037389)
- Citadel Advisors (CIK: 0001423053)
- Two Sigma Investments (CIK: 0001179392)

## Process

1. For each fund in the watchlist, fetch the most recent 13F filing:
   ```bash
   curl -H "x-api-key: $OMNI_DATASTREAM_API_KEY" \
     "https://api.secapi.ai/v1/ownership/13f?cik=0001067983&limit=1"

Fetch the previous quarter 13F for comparison:

curl -H "x-api-key: $OMNI_DATASTREAM_API_KEY" \
  "https://api.secapi.ai/v1/ownership/13f?cik=0001067983&limit=1&offset=1"

Compare holdings between quarters:
- New positions (in current but not previous)
- Exited positions (in previous but not current)
- Increased positions (shares up >10%)
- Decreased positions (shares down >10%)
Calculate portfolio concentration:
- Top 10 holdings by market value
- Percentage of total portfolio in top 10
Generate a formatted report with sections for each fund.

Output Format

Save the report as reports/13f-weekly-{date}.md with this structure:

# 13F Weekly Review - {date}

## Berkshire Hathaway
### New Positions
- TICKER: X,XXX shares ($X.XM)

### Exited Positions
- TICKER: was X,XXX shares

### Significant Changes
- TICKER: +XX% (X,XXX -> Y,YYY shares)

### Top 10 Holdings
| Rank | Ticker | Shares | Value | % of Portfolio |
...

## Bridgewater Associates
...

Guidelines

Only flag changes where share count moved more than 10%
Include dollar values where available
Note the filing date and period of report for each 13F
If a fund has not filed a new 13F since last run, note that

## Step 2 --- Install the skill

```bash
# From your project root
mkdir -p .claude/skills
cp weekly-13f-review.md .claude/skills/weekly-13f-review.md

Verify the skill is recognized:

claude skill list

You should see weekly-13f-review in the output.

Step 3 --- Test the skill manually

Run the skill once to verify it works:

claude "Run the weekly-13f-review skill for this week"

Claude Code will:

Call the OMNI Datastream API for each fund
Compare current and previous quarter holdings
Generate the report
Save it to reports/13f-weekly-2024-12-13.md

Review the output to make sure the data looks correct.

Step 4 --- Set up the cron schedule

Create a cron skill configuration to run the analysis on a schedule. Add this to .claude/skills/cron-13f-review.md:

---
name: cron-13f-review
description: "Scheduled trigger for weekly 13F review every Friday at 6 PM"
cron: "0 18 * * 5"
skill: weekly-13f-review
---

# Cron: Weekly 13F Review

Runs `weekly-13f-review` every Friday at 18:00 local time.

## On Success
- Save report to `reports/` directory
- Print summary to stdout

## On Failure
- Retry once after 5 minutes
- Log error to `reports/13f-errors.log`

Step 5 --- Configure the environment

Make sure your API key is available to scheduled runs. Add it to your shell profile or a .env file:

# In ~/.zshrc or ~/.bashrc
export OMNI_DATASTREAM_API_KEY="your-api-key-here"

Or create a .env file in your project root:

OMNI_DATASTREAM_API_KEY=your-api-key-here

Step 6 --- Verify the schedule

Check that the cron skill is registered:

claude skill list --scheduled

You should see:

cron-13f-review    0 18 * * 5    weekly-13f-review    active

Example report output

After the skill runs, you will find a report like this in reports/13f-weekly-2024-12-13.md:

# 13F Weekly Review - 2024-12-13

## Berkshire Hathaway
*Filed: 2024-11-14 | Period: 2024-09-30*

### New Positions
- SU (Suncor Energy): 5,250,000 shares ($210.5M)

### Exited Positions
- HP (Helmerich & Payne): was 2,604,637 shares
- PARA (Paramount Global): was 63,316,002 shares

### Significant Changes
- OXY (Occidental Petroleum): +12% (255,281,524 -> 285,915,108 shares)
- CB (Chubb Limited): -15% (27,033,784 -> 22,978,716 shares)

### Top 10 Holdings
| Rank | Ticker | Shares | Value ($M) | % of Portfolio |
|------|--------|--------|------------|----------------|
| 1 | AAPL | 400,000,000 | 91,600 | 28.1% |
| 2 | AXP | 151,610,700 | 42,451 | 13.0% |
| 3 | BAC | 680,233,587 | 30,274 | 9.3% |
| 4 | KO | 400,000,000 | 28,400 | 8.7% |
| 5 | CVX | 118,610,534 | 18,553 | 5.7% |
...

## Renaissance Technologies
*Filed: 2024-11-14 | Period: 2024-09-30*

### New Positions
- SMCI (Super Micro Computer): 1,200,000 shares ($48.6M)
...

Extending the workflow

Add email delivery

Modify the skill to send the report via email after generation:

## On Success
- Save report to `reports/` directory
- Email report to `team@yourcompany.com` using the configured SMTP skill

Add Slack posting

Add a step to post the executive summary to Slack:

# After generating the report, post a summary
curl -X POST -H "Content-Type: application/json" \
  -d "{\"text\": \"Weekly 13F Review is ready. $(head -20 reports/13f-weekly-$(date +%Y-%m-%d).md)\"}" \
  "$SLACK_WEBHOOK_URL"

Compare across quarters

Extend the skill to look at trends over multiple quarters instead of just the most recent change:

## Extended Process
- Fetch 13F data for the last 4 quarters
- Calculate rolling position changes
- Identify consistent accumulators and distributors

Troubleshooting

Problem	Solution
Skill not found	Verify the file is in `.claude/skills/` and the frontmatter `name` field is correct. Run `claude skill list` to confirm.
API key not available in cron	Make sure `OMNI_DATASTREAM_API_KEY` is exported in your shell profile, not just the current session.
Report is empty	Check that the CIKs in the watchlist are correct. Test with a single fund first using `curl` directly.
Cron not firing	Verify the cron expression `0 18 * * 5` is correct for your timezone. Check `claude skill list --scheduled`.
Stale data	13F filings are quarterly. If no new filing has been published since the last run, the report will show no changes. This is expected.

Next steps

Add more funds: Expand the watchlist in the skill file with additional CIKs.
Combine with insider data: Cross-reference 13F changes with insider trading patterns for a complete ownership picture.
Track specific stocks: Create a variant skill that monitors which funds hold a specific ticker and alerts when ownership changes.

See the Custom Skills guide for more on building and scheduling Claude Code skills.

Tutorials

​Scheduled SEC Analysis with Claude Code

​Prerequisites

​What you will build

​Step 1 --- Create the analysis skill

​Output Format

​Guidelines

​Step 3 --- Test the skill manually

​Step 4 --- Set up the cron schedule

​Step 5 --- Configure the environment

​Step 6 --- Verify the schedule

​Example report output

​Extending the workflow

​Add email delivery

​Add Slack posting

​Compare across quarters

​Troubleshooting

​Next steps