Add cookbook: Playwright with computer use fallback

[dprevoznik]

Summary

• Add a cookbook for starting browser agents with Playwright and switching to computer-use tools only for interactions that need screenshot-based control.
• Compare three handoff strategies: Per-Tool Limit, Total Tool-Call Limit, and Model-Directed Handoff.
• Include complete TypeScript examples with matching constants, session IDs, filenames, comments, prompts, and log labels.
• Add browsers/playwright-computer-use-fallback.mdx to the docs navigation.

Test plan

• Validate docs.json with jq empty docs.json.
• Run PUPPETEER_SKIP_DOWNLOAD=true npx --yes mint broken-links.
• Run mint dev --port 3000 and verify /browsers/playwright-computer-use-fallback returns HTTP 200 and renders all three approach names.

---

Note

Low Risk
Documentation-only changes with no product or API behavior impact; the Control intro now favors Playwright-first guidance, which may diverge slightly from later sections on the same page that still describe computer-use-first patterns.

Overview
Adds a new cookbook at /browsers/playwright-computer-use-fallback that documents using @onkernel/browser-loop to run DOM-based Playwright tools first and switch to screenshot-based computer-use tools when interactions (e.g. pointer drag-and-drop) fail silently. It walks through one magnitasks.com Kanban task and three handoff patterns: per-tool attempt limits, total Playwright tool-call limits, and model-directed loop.toolsets.mixed() with prompt steering, including full TypeScript samples (KERNEL browser, replay recording, compiled.apply(harness)).

Navigation and positioning: registers the page in docs.json under Intermediate browser guides, and updates introduction/control so the agent recommendation points at this guide (Playwright first, computer use fallback) instead of treating the two modes as peer equals in the opening paragraph.

^{Reviewed by Cursor Bugbot for commit 0bb8281. Bugbot is set up for automated code reviews on this repo. Configure here.}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after ae2154a. The PR is still documentation-only: a new cookbook page (browsers/cua-fallback.mdx) and one docs.json sidebar entry. No application code, API, auth, CI, or infrastructure changes.

The new commit rewrites a single prose sentence to use generic wording instead of naming third-party agent SDKs. No new files, nav changes, or executable paths.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after fb68cc0. The PR remains documentation-only: one new cookbook page and one docs.json sidebar entry. No application code, API, auth, CI, or infrastructure changes.

The new commit renames browsers/cua-fallback.mdx → browsers/code-mode-fallback.mdx and updates copy/identifiers (playwright mode → code mode, CUA → computer use, matching docs.json path). Same page, same nav slot, no new executable paths.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after 8e9d59f. The PR remains documentation-only: one new cookbook page (browsers/code-mode-fallback.mdx) and one docs.json sidebar entry after Playwright Execution. No application code, API, auth, CI, or infrastructure changes.

The new commit rewrites two paragraphs in Picking a harness to describe browser-loop / compiled.apply() as explanation rather than endorsement, and to state that the same handoff pattern applies to other harnesses. No new files, nav changes, or executable paths.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after 37cb336. The PR remains documentation-only: one new cookbook page (browsers/code-mode-fallback.mdx) and one docs.json sidebar entry after Playwright Execution. No application code, API, auth, CI, or infrastructure changes.

The new commit restores fuller @onkernel/browser-loop example snippets (replay start/stop, longer comments, playwright/CUA naming aligned with the library) and keeps the general code-mode / computer-use framing. Same page, same nav slot, no new files or executable paths in this repo.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after 608db5c. The PR remains documentation-only: one new cookbook page (browsers/code-mode-fallback.mdx) and one docs.json sidebar entry after Playwright Execution. No application code, API, auth, CI, or infrastructure changes.

The new commit rewrites a single sentence in Code mode vs. computer use so code mode is framed as the general DOM-ref approach and playwright mode as browser-loop's implementation of it. Same page, same nav slot, no new files or executable paths in this repo.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

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[AnnaXWang]

Hm I think the original version using "Playwright" is clearer, since raf defines code mode as give your agent the ability to write code. So I think we can write a separate guide focused on code mode and revert this all to Playwright, i'm going through now and will push up a commit

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after 3ed9482. The PR remains documentation-only: one new cookbook page (browsers/playwright-cua-fallback.mdx) and one docs.json sidebar entry after Playwright Execution. No application code, API, auth, CI, or infrastructure changes.

The new commit renames browsers/code-mode-fallback.mdx → browsers/playwright-cua-fallback.mdx, retitles the page to Using Playwright with CUA Fallback, and swaps remaining “code mode” wording to Playwright/CUA. It also adds a short Playwright intro. Same cookbook, same nav slot, no new executable paths in this repo.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after 167fdb2. The PR remains documentation-only: one new cookbook page (browsers/playwright-cua-fallback.mdx) and one docs.json sidebar entry after Playwright Execution. No application code, API, auth, CI, or infrastructure changes.

The new commit rewords one intro sentence (tools → frameworks) and adds a two-sentence definition of an agent tool vs. a toolset under Playwright vs. CUA. Same page, same nav slot, no new files or executable paths in this repo.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after b1a59b1. The PR remains documentation-only: one new cookbook page (browsers/playwright-cua-fallback.mdx) and one docs.json sidebar entry after Playwright Execution. No application code, API, auth, CI, or infrastructure changes. No CODEOWNERS file in the repo.

The new commit is copy and branding on that same page: title/description wording, CUA → Computer Use in headings and prose, Kernel → KERNEL in comments and example identifiers, and a short harness-section rewrite. Same cookbook, same nav slot, no new files or executable paths in this repo.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after 5f33aa2. The PR remains documentation-only: one new cookbook page (browsers/playwright-computer-use-fallback.mdx) and one docs.json sidebar entry after Playwright Execution. No application code, API, auth, CI, or infrastructure changes. No CODEOWNERS file in the repo.

The new commit renames browsers/playwright-cua-fallback.mdx → browsers/playwright-computer-use-fallback.mdx, updates the nav slug to match, and standardizes handoff wording (CUA → computer use; Approach A/B/C → Per-Tool Attempt Limit / Total Tool-Call Limit / Model-Directed Handoff). Example snippet identifiers, filenames, log labels, and variable names were renamed to match. Same cookbook, same nav slot, no new executable paths in this repo.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[AnnaXWang]

I updated the Playwright fallback cookbook to make the terminology clearer. I renamed the three strategies to Per-Tool Limit, Total Tool-Call Limit, and Model-Directed Handoff, let's discuss in Slack if we want to update this more.

I also realized that CUA was an overloaded term. I replaced it everywhere with “computer use” or “computer-use tools” throughout the guide and code examples.

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after 575fd95. The PR remains documentation-only: one new cookbook page (browsers/playwright-computer-use-fallback.mdx) and one docs.json sidebar entry after Playwright Execution. No application code, API, auth, CI, or infrastructure changes. No CODEOWNERS file in the repo.

The new commit is copy-only on that same page: Per-Tool Attempt Limit → Per-Tool Limit in headings, tables, prose, example comments, session IDs, and suggested filenames. Same cookbook, same nav slot, no new files or executable paths in this repo.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook page; existing pages unchanged
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after c9b3c7e. The PR remains documentation-only. Current files:

• new cookbook page browsers/playwright-computer-use-fallback.mdx
• docs.json sidebar entry after Playwright Execution
• one-sentence copy change on introduction/control.mdx

No application code, API, auth, CI, or infrastructure changes. No CODEOWNERS file in the repo.

The new commit only updates the Control intro lead: it points agents at Playwright first with a computer-use fallback, and adds a link to the new cookbook. Same docs surface (Mintlify pages + nav), no new executable paths in this repo.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook plus a one-line intro recommendation/link
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Stale comment

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after 1f76b71 (merge of main into this branch). The PR remains documentation-only. Current files unique to this branch vs main:

• new cookbook page browsers/playwright-computer-use-fallback.mdx
• docs.json sidebar entry after Playwright Execution
• one-sentence copy change on introduction/control.mdx

No application code, API, auth, CI, or infrastructure changes. No CODEOWNERS file in the repo.

The new commit is a merge of already-landed main (Foreman's Vercel KB link and related docs). It does not add files or behavior to this PR's unique surface.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook plus a one-line intro recommendation/link
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Risk assessment: Very Low

Decision: Approval stands (not re-approved; risk did not increase)

Re-evaluated after 0bb8281. The PR remains documentation-only. Current files unique to this branch vs main:

• new cookbook page browsers/playwright-computer-use-fallback.mdx
• docs.json sidebar entry after Playwright Execution
• copy change on introduction/control.mdx

No application code, API, auth, CI, or infrastructure changes. No CODEOWNERS file in the repo.

The new commit only rewords the Control intro link to the same cookbook (playwright w/ computer use fallback). Same docs surface (Mintlify pages + nav), no new executable paths in this repo.

Factor	Assessment
Codepaths modified	Docs content + sidebar nav only
Blast radius	New Intermediate cookbook plus an intro recommendation/link
Complexity	Example TypeScript snippets for readers; not executed by this repo
Infrastructure impact	None
Production / shared systems	None
CODEOWNERS	No CODEOWNERS file in the repo

Example systemPrompt strings in the cookbook are illustrative copy, not deployed model instructions for this site.

Prior approval on affd44c remains in effect. Risk did not increase, so approval is not dismissed and is not re-issued.

  

_{Sent by Cursor Automation: Assign PR reviewers}

[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit 0bb8281. Configure here.}

[cursor]

Control intro mislinks Playwright Execution

Medium Severity

The Control intro now recommends “playwright execution” and links to the new cookbook, but that page teaches @onkernel/browser-loop DOM tools (loop.toolsets.browser()), not kernel.browsers.playwright.execute(). The following “Both run co-located… avoid… CDP” sentence is no longer true of that path, and it contradicts this page’s later “computer controls for interaction, playwright execution for structured data” guidance.

 

^{Triggered by learned rule: Promote Playwright Execution API over direct CDP connections in examples}

^{Reviewed by Cursor Bugbot for commit 0bb8281. Configure here.}