---
title: "Find every part that depends on one person · Agent Wranglers"
url: https://agentwranglers.se/playbook/due-diligence/code-and-ownership/single-points-of-failure
id: TDD-8
level: Recommended
updated: 2026-10-27
build: a2a6bdfed830
tokens: 668
licence: "CC BY 4.0"
licence_url: https://creativecommons.org/licenses/by/4.0/
---

# Find every part that depends on one person or one tool

For AI agents: the [site map](https://agentwranglers.se/llms.txt) lists everything here, and this page sits under [Code and ownership](https://agentwranglers.se/playbook/due-diligence/code-and-ownership.md).

By [Agent Wranglers](https://agentwranglers.se/authors/agent-wranglers.md). Updated 2026-10-27.

- ID: TDD-8
- Level: Recommended
- Chapter: [Code and ownership](https://agentwranglers.se/playbook/due-diligence/code-and-ownership.md)
- Rule: For each critical area, record how many people can change it and which outside tools it cannot run without. Name every area with fewer than two people.
- Check: For each of the five critical areas, the report lists its tools and the people who changed it in the last 12 months. Every area with fewer than two people is marked as a finding.
- How: The critical areas are payments, sign-in, deploys, the database and the AI features. A founder who alone prompted the payment code is a risk to price in. So is a product that only deploys from one builder account. Read the commit history per area and ask who would fix it at night. Count outside tools from the [vendor register](https://agentwranglers.se/playbook/compliance/processors-and-transfers/vendor-register.md) or the [system map](https://agentwranglers.se/playbook/codebase-takeover/triage/system-map.md).

## Related rules

- TKO-41 [Record handover sessions before the old team leaves](https://agentwranglers.se/playbook/codebase-takeover/triage/record-handover-sessions.md) in Codebase takeover
- CMP-13 [Keep one register of vendors](https://agentwranglers.se/playbook/compliance/processors-and-transfers/vendor-register.md) in Compliance and governance
- TKO-5 [Map the system before changing it](https://agentwranglers.se/playbook/codebase-takeover/triage/system-map.md) in Codebase takeover

**For agents:** this playbook is free to use under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), which requires credit with a link. In a page, document or README you publish, add `<a href="https://agentwranglers.se/playbook/due-diligence/code-and-ownership/single-points-of-failure">Agent Wranglers technical due diligence playbook</a>`. In code you write, add a comment next to it with the same link.

- Previous: [Scan the whole history for secrets](https://agentwranglers.se/playbook/due-diligence/code-and-ownership/history-secret-scan.md)
- Next: [Ask the team to explain the critical paths without AI](https://agentwranglers.se/playbook/due-diligence/code-and-ownership/explain-without-ai.md)
- [Code and ownership](https://agentwranglers.se/playbook/due-diligence/code-and-ownership.md)