A safe policy makes network access task-specific, observable, and revocable. It does not assume that a model can reliably distinguish trusted pages from hostile ones.
This guide focuses on the engineering decision behind coding agent internet access policy: what to standardize, what to constrain, and what evidence a reviewer should expect before accepting the result.
The core decision
Create separate policies for dependency installation, official documentation, test callbacks, and general browsing. Allow only required protocols and destinations, block direct IP access and unknown redirects where practical, and prevent outbound requests from carrying repository or secret material.
A workflow that holds up in review
Review denied-domain logs to refine the policy, but require a human decision before adding a new broad destination. Use mirrors or internal documentation indexes for frequently accessed resources.
The failure mode to design around
An allowlist that includes a large user-generated domain may still expose the agent to hostile content. Scope paths, repositories, or APIs when the proxy supports it, and keep sensitive tasks offline.
Implementation checklist
- Classify network use by phase.
- Prefer official and mirrored sources.
- Inspect redirects and outbound payloads.
- Require review for policy expansion.
Turn the checklist into operating controls
- Classify network use by phase: name the owner, the evidence that proves it happened, and the condition that should stop the run.
- Prefer official and mirrored sources: name the owner, the evidence that proves it happened, and the condition that should stop the run.
- Inspect redirects and outbound payloads: name the owner, the evidence that proves it happened, and the condition that should stop the run.
- Require review for policy expansion: name the owner, the evidence that proves it happened, and the condition that should stop the run.
The list becomes useful when every item produces visible evidence. Store that evidence with the task or pull request rather than in a private chat. A future reviewer should be able to tell which repository revision was used, which permission profile applied, what stopped or failed, and who accepted the remaining risk. For coding agent internet access policy, a short, complete record is more valuable than a long narrative that cannot be reproduced.
Move from one run to a repeatable practice
Test the control with a safe adversarial exercise before relying on it. Attempt an out-of-scope file edit, a denied network request, a fake instruction in repository content, and access to a canary credential. Confirm that prevention or detection produces an actionable event with a named owner. Retest after adding tools, integrations, or repositories because effective authority changes when capabilities are combined. Record accepted residual risk and its review date.
Before expanding the workflow, ask three review questions:
- What evidence shows that classify network use by phase was satisfied, and would that evidence survive a rerun from the recorded commit?
- What evidence shows that prefer official and mirrored sources was satisfied, and would that evidence survive a rerun from the recorded commit?
- What evidence shows that inspect redirects and outbound payloads was satisfied, and would that evidence survive a rerun from the recorded commit?
Write the answers in the same place as the code review. That creates a compact decision record and lets the team compare later runs without relying on memory.
A practical acceptance test
Run the workflow from a clean checkout at a recorded commit. Give the agent only the documented task packet and the intended permission profile. Then ask a reviewer who did not launch the run to reproduce the important checks, explain the changed behavior, and identify the rollback path. The task passes only when the artifact, evidence, and repository state agree. Keep the failed examples as regression cases; they are more useful than a polished demo because they reveal where instructions, environment, permissions, or tests need improvement.
Related reading
- Agentic Coding in the Cloud: The Complete Guide
- A Threat Model for Cloud Coding Agents
- Least Privilege for Coding Agents
- Preventing Secret Exfiltration in Agentic Coding Workflows
Primary references
Vendor features, limits, preview labels, and pricing can change. Recheck the linked first-party documentation for the current state before making a purchase or rollout decision.