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feat: Integrate CrUX data into performance trace summaries#733

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OrKoN merged 32 commits intomainfrom
crux-for-trace
Feb 5, 2026
Merged

feat: Integrate CrUX data into performance trace summaries#733
OrKoN merged 32 commits intomainfrom
crux-for-trace

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@paulirish paulirish commented Jan 6, 2026

We upgrade the performance trace tools to include real-user experience data from the Chrome User Experience Report (CrUX).

https://developer.chrome.com/docs/crux
https://developer.chrome.com/docs/crux/methodology

Deets

  • When a trace is stopped, the server now extracts the primary navigation URLs from the trace (determined by insightSets).
  • It calls the public CrUX API to fetch field metrics (LCP, INP, CLS) for each unique URL/Origin.
  • The formatting of crux data is handled by upstream TraceFormatter, but it looks like this:
Metrics (field / real users):
  - LCP: 2595 ms (scope: url)
  - LCP breakdown:
    - TTFB: 1273 ms (scope: url)
    - Load delay: 86 ms (scope: url)
    - Load duration: 451 ms (scope: url)
    - Render delay: 786 ms (scope: url)
  - INP: 140 ms (scope: url)
  - CLS: 0.06 (scope: url)
  - The above data is from CrUX–Chrome User Experience Report. It's how the page performs for real users.
  - The values shown above are the p75 measure of all real Chrome users
  - The scope indicates if the data came from the entire origin, or a specific url
  - Lab metrics describe how this specific page load performed, while field metrics are an aggregation of results from real-world users. Best practice is to prioritize metrics that are bad in field data. Lab metrics may be better or worse than fields metrics depending on the developer's machine, network, or the actions performed while tracing.

Privacy Considerations:

  • Updates the server README to inform users that performance analysis tools may send trace URLs to the Google CrUX API.
  • Adds a notification message to the server startup logs regarding the CrUX API interaction.

Doc: go/crux-in-bifrost
Fixes b/446630695

paulirish and others added 17 commits December 22, 2025 14:21
@paulirish
revert these lockfile changes
be31b47 
Change-Id: Ibda3954500250fa9c2d0ae95dd996409ea525080
@paulirish
implemented but imma change it
9623ae6 
Change-Id: Ib9b76305409bb660a25182497d9b54591e2297a0
@paulirish
collapsed to a single setting
31a6cf1 
Change-Id: I3886ba86705ce423ccf8024133bc58fff16fa6c8
@paulirish
remove toggle tool. bump up timeouts while i investigate them
1f17741 
Change-Id: I921880b40788863151962d13dc9838c4793a840f
@paulirish
ensureCrux for test
de66b44 
Change-Id: I94c55d08bad7c58b28a5febccdc126dc0b012e5f
@paulirish
manual test yayyyyyyyyyyy
a2894a9 
Change-Id: I70fa78a46ebb1bc43be66dcd80177cec2ab34f1c
@paulirish
universe mgr added to ctx
e2da11a 
Change-Id: Id8ff5120b5f02cd57ed42427b182763afbf65dff
@paulirish
settings is resolve but now we need to give cruxmgr some data to report
7e71d8f 
Change-Id: I22e211eebdca6bf25878cb4dd4182d9b6ca34cf8
@paulirish
drop util crux. trying to get proper data from real thing
647f0d9 
Change-Id: Ie1905a1b746cce82b27dfe89c56d2b591c050291
@paulirish
new endpoint. will work when i tweak api in GCP C
eb5bc51 
Change-Id: I331aa991818b151e7b4080490475736afd30120f
@paulirish
Merge branch 'main' into crux-for-trace
94ac77c 
Change-Id: I2e45c268b8510658b4ece06f52a7bd67b5154b2a
@paulirish
Merge remote-tracking branch 'origin/main' into crux-for-trace
44687f9 
Change-Id: I04829e52b7e38bf4384b6db89f977abe518d7b5e
@paulirish
works
7d8ae17 
Change-Id: I2b5dcda9b32db8ec0ca1270e267edfeb562ff7b5
@paulirish
mock fetch to avoid network RT in test
9280192 
Change-Id: I5e824dbb077b94accb65420d97f5fc3de61fbd53
@paulirish
drop diff
295b192 
Change-Id: Ibf10ea910e34bac5fc44bf13760ceb971680dd35
@paulirish
use proper export
1662b6d 
Change-Id: I8eff31fd3b8d01f7ac466ed22117696844227ac4
@paulirish
prep for crrev.com/c/7421201
4cef374 
Change-Id: I5b9c78336bf0d7ca8ae42f62fc59bfe28da628ee
@OrKoN
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OrKoN commented Jan 13, 2026

@paulirish I have updated the devtools-frontend dependency today so it should be ready to be rebased

paulirish and others added 2 commits January 13, 2026 05:50
@paulirish
Merge branch 'main' into crux-for-trace
d892a26
@paulirish
skip manager? nahh
009064a 
Change-Id: Ib6eacf5cc90e858b3c2cbce67ceb41f4d35b0065
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paulirish commented Jan 14, 2026

@paulirish I have updated the devtools-frontend dependency today so it should be ready to be rebased

Danke! It's up to date now.

@paulirish paulirish requested a review from OrKoN January 14, 2026 23:01
OrKoN
OrKoN reviewed Jan 15, 2026
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OrKoN commented Jan 28, 2026

@paulirish is it possible to update the implementation to make CrUX integration conditional on a CLI flag (can be enabled by default for now)?

paulirish
paulirish commented Jan 28, 2026
View reviewed changes
@paulirish
Merge remote-tracking branch 'origin/main' into crux-for-trace
0f371af 
Change-Id: I91338964fd926022c6d88dc35308479370a3fb80
@paulirish
logger
ce92886 
Change-Id: I19d3ac21253fb67ae8e82ac1da2414424dc05b21
@paulirish
drop univermgr addition as its already done
446f32f 
Change-Id: I7cff8cff76bbd606dde471847d841c5fb0c05b1d
@paulirish
add --performance-crux flag, defaulted to true
010125b 
Change-Id: Ia6dcaf83b12fe44a5167a5c7c8fb7e40276af61c
@paulirish
Merge branch 'crux-for-trace' of github.com:ChromeDevTools/chrome-dev…
a2b167e 
…tools-mcp into crux-for-trace

Change-Id: Ie34ac6b674332a1b941966692f7fe9177b76b02e
@paulirish
fix cli test
a6a45a2 
Change-Id: I2b47d8436a7d864ee1483116bf282081b8144031
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paulirish commented Jan 29, 2026

@paulirish is it possible to update the implementation to make CrUX integration conditional on a CLI flag (can be enabled by default for now)?

done

@OrKoN OrKoN enabled auto-merge February 5, 2026 07:15
@OrKoN OrKoN added this pull request to the merge queue Feb 5, 2026
Merged via the queue into main with commit b747f9d Feb 5, 2026
31 of 33 checks passed
@OrKoN OrKoN deleted the crux-for-trace branch February 5, 2026 07:32
@browser-automation-bot browser-automation-bot mentioned this pull request Feb 5, 2026
Merged
github-merge-queue bot pushed a commit that referenced this pull request Feb 10, 2026
@browser-automation-bot
chore(main): release chrome-devtools-mcp 0.17.0 (#892)
6a3ca98 
🤖 I have created a release *beep* *boop*
---


##
[0.17.0](chrome-devtools-mcp-v0.16.0...chrome-devtools-mcp-v0.17.0)
(2026-02-10)


### 🎉 Features

* include Error.cause chain for uncaught errors and logged Errors
([#906](#906))
([05b01ec](05b01ec))
* Integrate CrUX data into performance trace summaries
([#733](#733))
([b747f9d](b747f9d))
* show message and stack trace in details when console.log'ging Error
objects
([#902](#902))
([ffa00da](ffa00da))


### 🛠️ Fixes

* console formatter hides frames from ignored scripts
([#927](#927))
([8e2380b](8e2380b))
* limit stack traces to 50 lines
([#923](#923))
([caea23a](caea23a))


### 📄 Documentation

* add macOS Web Bluetooth troubleshooting note
([#930](#930))
([3c9528b](3c9528b)),
closes
[#917](#917)

---
This PR was generated with [Release
Please](https://github.com/googleapis/release-please). See
[documentation](https://github.com/googleapis/release-please#release-please).
wolfib pushed a commit to wolfib/chrome-devtools-mcp that referenced this pull request Mar 10, 2026
@paulirish @OrKoN @wolfib
feat: Integrate CrUX data into performance trace summaries (ChromeDev…
18c7231 
…Tools#733)

We upgrade the performance trace tools to include real-user experience
data from the Chrome User Experience Report (CrUX).

https://developer.chrome.com/docs/crux
https://developer.chrome.com/docs/crux/methodology

### Deets

* When a trace is stopped, the server now extracts the primary
navigation URLs from the trace (determined by insightSets).
* It calls the public CrUX API to fetch field metrics (LCP, INP, CLS)
for each unique URL/Origin.
* The formatting of crux data is handled by upstream TraceFormatter, but
it looks like this:

```md
Metrics (field / real users):
  - LCP: 2595 ms (scope: url)
  - LCP breakdown:
    - TTFB: 1273 ms (scope: url)
    - Load delay: 86 ms (scope: url)
    - Load duration: 451 ms (scope: url)
    - Render delay: 786 ms (scope: url)
  - INP: 140 ms (scope: url)
  - CLS: 0.06 (scope: url)
  - The above data is from CrUX–Chrome User Experience Report. It's how the page performs for real users.
  - The values shown above are the p75 measure of all real Chrome users
  - The scope indicates if the data came from the entire origin, or a specific url
  - Lab metrics describe how this specific page load performed, while field metrics are an aggregation of results from real-world users. Best practice is to prioritize metrics that are bad in field data. Lab metrics may be better or worse than fields metrics depending on the developer's machine, network, or the actions performed while tracing.
 ```
 
**Privacy Considerations:**

*   Updates the server README to inform users that performance analysis tools may send trace URLs to the Google CrUX API.
*   Adds a notification message to the server startup logs regarding the CrUX API interaction.


Doc: go/crux-in-bifrost 
Fixes b/446630695

---------

Co-authored-by: Alex Rudenko <alexrudenko@chromium.org>
Co-authored-by: Alex Rudenko <OrKoN@users.noreply.github.com>
wolfib pushed a commit to wolfib/chrome-devtools-mcp that referenced this pull request Mar 10, 2026
@browser-automation-bot @wolfib
chore(main): release chrome-devtools-mcp 0.17.0 (ChromeDevTools#892)
607d37a 
🤖 I have created a release *beep* *boop*
---


##
[0.17.0](ChromeDevTools/chrome-devtools-mcp@chrome-devtools-mcp-v0.16.0...chrome-devtools-mcp-v0.17.0)
(2026-02-10)


### 🎉 Features

* include Error.cause chain for uncaught errors and logged Errors
([ChromeDevTools#906](ChromeDevTools#906))
([05b01ec](ChromeDevTools@05b01ec))
* Integrate CrUX data into performance trace summaries
([ChromeDevTools#733](ChromeDevTools#733))
([b747f9d](ChromeDevTools@b747f9d))
* show message and stack trace in details when console.log'ging Error
objects
([ChromeDevTools#902](ChromeDevTools#902))
([ffa00da](ChromeDevTools@ffa00da))


### 🛠️ Fixes

* console formatter hides frames from ignored scripts
([ChromeDevTools#927](ChromeDevTools#927))
([8e2380b](ChromeDevTools@8e2380b))
* limit stack traces to 50 lines
([ChromeDevTools#923](ChromeDevTools#923))
([caea23a](ChromeDevTools@caea23a))


### 📄 Documentation

* add macOS Web Bluetooth troubleshooting note
([ChromeDevTools#930](ChromeDevTools#930))
([3c9528b](ChromeDevTools@3c9528b)),
closes
[ChromeDevTools#917](ChromeDevTools#917)

---
This PR was generated with [Release
Please](https://github.com/googleapis/release-please). See
[documentation](https://github.com/googleapis/release-please#release-please).
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