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+<!-- page-journey: all -->
+<!-- page-adventure: advanced -->
+<!--
+<research-metadata>
+  <focus>Network egress control in agentic workflows — the top-level `network:` frontmatter field, ecosystem identifiers, custom domain allowlists, and `blocked` entries</focus>
+  <sources>
+    <source>https://github.github.com/gh-aw/llms.txt (downloaded to /tmp/gh-aw/data/llms.txt)</source>
+    <source>https://github.github.com/gh-aw/reference/network/</source>
+    <source>https://github.github.com/gh-aw/reference/sandbox/</source>
+    <source>https://github.github.com/gh-aw/reference/frontmatter/</source>
+  </sources>
+  <rationale>The existing curriculum (steps 1-30) explains the firewall conceptually in the security step and mentions `network.allowed` in side quests, but no step has learners configure it. Learners who add a data source, an MCP server, or a package install hit blocked requests or `(redacted)` URLs and have no hands-on model for fixing them safely. The gh-aw network reference documents `network: defaults`, selective `allowed` lists, ecosystem identifiers such as `python` and `node`, `blocked` entries that take precedence, and the fact that the same allowlist also drives content sanitization. This step turns those concepts into one concrete exercise: start from least privilege, add exactly the domains a workflow needs, and verify the result.</rationale>
+</research-metadata>
+-->
+
+# Control Which Domains Your Agent Can Reach
+
+> _Give your agent the internet access it needs, and nothing more._
+
+## :dart: What You'll Do
+
+You'll configure the [`network:` field](https://github.github.com/gh-aw/reference/network/) on one of your workflows so it can reach only the domains you list. When you finish, you'll have a least-privilege allowlist and know how to fix a blocked request without opening everything up.
+
+Why this matters: the agent runs inside the [sandbox firewall](https://github.github.com/gh-aw/reference/sandbox/), so any request to an unlisted domain is blocked. That protects you from data exfiltration, but it also means every new data source or tool needs a deliberate allowlist entry.
+
+## :clipboard: Before You Start
+
+- You completed [Connect a Live Data Source to Your Workflow](16-connect-data-source.md) or have any workflow that calls an external service.
+- You can compile workflows with `gh aw compile`.
+
+## Steps
+
+### Check your current default
+
+If a workflow has no `network:` field, it uses `network: defaults`, which allows only basic infrastructure such as certificates, JSON schema, and common package mirrors. Open your workflow and confirm whether it sets `network:` already.
+
+### Allow only what the workflow needs
+
+Add a `network:` block to the frontmatter. Mix ecosystem identifiers with specific domains:
+
+```markdown .github/workflows/daily-status.md
+---
+on:
+  schedule: daily
+permissions:
+  contents: read
+network:
+  allowed:
+    - defaults
+    - github
+    - "api.example.com"
+---
+```
+
+Listed domains also match their subdomains. Identifiers such as `python` or `node` allow a whole package ecosystem, so prefer a specific domain when the workflow only calls one API.
+
+Recompile:
+
+```bash
+gh aw compile
+```
+
+### Block a domain explicitly
+
+Use `blocked` to exclude an ecosystem or domain. Blocked entries take precedence over `allowed`:
+
+```markdown .github/workflows/daily-status.md
+network:
+  allowed:
+    - defaults
+    - github
+    - node
+  blocked:
+    - "cdn.example.com"
+```
+
+### Fix a blocked request
+
+1. Run the workflow with `gh aw run daily-status`.
+2. If the agent reports a failed request or a URL shows as `(redacted)` in its output, note the domain.
+3. Add only that domain to `network.allowed`, recompile, and run again.
+
+The same allowlist controls network egress and which URLs survive content sanitization, so one entry fixes both.
+
+### Lock it down completely
+
+For a workflow that only reads repository data through GitHub tools, you can block all network access:
+
+```markdown .github/workflows/daily-status.md
+network: {}
+```
+
+> [!NOTE]
+> Hosted web search and fetch tools from Claude and Codex run on provider infrastructure, so `network.allowed` doesn't constrain them. See the [network reference](https://github.github.com/gh-aw/reference/network/) for the separate `hosted-web` policy.
+
+## :white_check_mark: Checkpoint
+
+- [ ] Your workflow has an explicit `network:` block and the lock file was recompiled
+- [ ] You can explain the difference between `defaults`, `allowed`, `blocked`, and `network: {}`
+- [ ] You fixed or deliberately avoided a blocked request by adding only the specific domain needed
+- [ ] You committed both the `.md` and `.lock.yml` files
+
+<!-- journey: all -->
+Want to choose another branch from the workshop hub? Return to [What's Next? Keep Exploring](14-next-steps.md).
+<!-- /journey -->
diff --git a/workshop/README.md b/workshop/README.md
index 97a99f9a..ff9ae214 100644
--- a/workshop/README.md
+++ b/workshop/README.md
@@ -42,6 +42,7 @@ A hands-on workshop that takes you from zero to a fully automated, AI-powered wo
 | 28 | [Orchestrate Multiple Agentic Workflows](28-orchestrate-workflows.md) |
 | 29 | [Teach Your Agent Domain Knowledge with Skills](29-skills-and-domain-knowledge.md) |
 | 30 | [Preview Your Workflow's Writes with Staged Mode](30-preview-with-staged-mode.md) |
+| 31 | [Control Which Domains Your Agent Can Reach](31-control-network-access.md) |
 
 ## Optional Side Quests