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This page explains how you can provide feedback on the accuracy of the
assessments created by reCAPTCHA. With this information,
reCAPTCHA can tune your site-specific model and provide
improved performance for your site over time.
When to annotate assessments
reCAPTCHA provides a score when creating an assessment that
helps you understand the level of risk user interactions pose.
Later, when your site has more information about user interactions
to determine if the interaction was legitimate or fraudulent, you can confirm or
correct reCAPTCHA's assessment. To do this, you send the
reCAPTCHA assessment IDs back to Google labeled as LEGITIMATE
or FRAUDULENT.
Confirming or correcting
reCAPTCHA's assessment improves the performance of
reCAPTCHA for your site.
To improve the performance of reCAPTCHA, you can confirm the
annotations for true positives and true negatives in addition to the
annotations for potential assessment errors.
For example, for a user who successfully authenticated using
a 2-factor-authentication method and received a high reCAPTCHA score, you can
annotate the assessment as LEGITIMATE. Alternatively, if reCAPTCHA
score was low and your site determined that the interaction was fraudulent or
abusive, you can annotate the assessment as FRAUDULENT.
The following list shows additional information about some sample user
interactions that indicate whether a user interaction is legitimate or
fraudulent:
Credit card chargebacks or other concrete evidence of fraud indicate that an
earlier financial transaction was fraudulent.
A new account that sends messages that are flagged as spam by other users
might indicate that the account creation was fraudulent.
A support case filed if a user has difficulty logging in to their account
might indicate that the login attempt is legitimate.
A purchase or booking on a site that uses reCAPTCHA to
defend against scraping might indicate that the user is legitimate.
Before you begin
Ensure that you have the following Identity and Access Management role:
reCAPTCHA Enterprise Agent (roles/recaptchaenterprise.agent).
Depending on where you have set up reCAPTCHA, complete the
appropriate step:
For WAF integrations, you can retrieve the unique assessment ID from the
reCAPTCHA token. The unique assessment ID is the
unique alphanumeric string of 16 characters that appears at the end of the
reCAPTCHA token after :U=. For example, if the reCAPTCHA token is
.................U=6ZZZZe73fZZZZZZ0, then the assessment ID is 6ZZZZe73fZZZZZZ0.
Annotate an assessment
Determine the information and labels to add in the request JSON body
depending on your use case.
The following table lists the labels and values that you can use to annotate
events:
Label
Description
Request example
reasons
Optional. A label to support your
assessments.
Provide real-time event details in the
reasons label in a few seconds or minutes after the event
because they influence real-time detection.
Example: To detect account takeovers, annotate if the entered
password was correct with CORRECT_PASSWORD or
INCORRECT_PASSWORD values. If you deployed your own MFA,
you can add the following values: INITIATED_TWO_FACTOR, and
PASSED_TWO_FACTOR or FAILED_TWO_FACTOR.
{
"reasons": ["INCORRECT_PASSWORD"]
}
annotation
Optional. A label to indicate the
legitimacy of assessments.
Provide facts about login and
registration events to validate or correct your risk assessments in the
annotation label.
Possible values: LEGITIMATE
or FRAUDULENT.
You can send this information at any time or as part of a batch job.
However, we recommend sending this information in a few seconds or minutes
after the event because they influence real-time detection.
Before using any of the request data,
make the following replacements:
ASSESSMENT_ID: Value of the name field returned from the projects.assessments.create call.
ANNOTATION_LABEL: The label to indicate whether the assessment is legitimate or fraudulent.
Possible values are LEGITIMATE or FRAUDULENT.
ANNOTATION_REASON: Describes the context for the annotation that was chosen for this assessment.
To learn about possible values, see reasons for annotating an assessment.
HTTP method and URL:
POST https://recaptchaenterprise.googleapis.com/v1/ASSESSMENT_ID:annotate
You should receive a successful status code (2xx) and an empty response.
API key
Before using any of the request data,
make the following replacements:
ASSESSMENT_ID: Value of the name field returned from the projects.assessments.create call
ANNOTATION_LABEL: The label to indicate whether the assessment is legitimate or fraudulent.
Possible values are LEGITIMATE or FRAUDULENT.
ANNOTATION_REASON: Describes the context for the annotation that was chosen for this assessment.
To learn about possible values, see reasons for annotating an assessment.
HTTP method and URL:
POST https://recaptchaenterprise.googleapis.com/v1/projects/PROJECT_ID/assessments/ASSESSMENT_ID:annotate?key=API_KEY
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-25 UTC."],[],[],null,["# Annotate assessments\n\nThis page explains how you can provide feedback on the accuracy of the\nassessments created by reCAPTCHA. With this information,\nreCAPTCHA can tune your site-specific model and provide\nimproved performance for your site over time.\n\nWhen to annotate assessments\n----------------------------\n\nreCAPTCHA provides a score when creating an assessment that\nhelps you understand the level of risk user interactions pose.\nLater, when your site has more information about user interactions\nto determine if the interaction was legitimate or fraudulent, you can confirm or\ncorrect reCAPTCHA's assessment. To do this, you send the\nreCAPTCHA assessment IDs back to Google labeled as `LEGITIMATE`\nor `FRAUDULENT`.\nConfirming or correcting\nreCAPTCHA's assessment improves the performance of\nreCAPTCHA for your site.\n\nTo improve the performance of reCAPTCHA, you can confirm the\nannotations for **true positives** and **true negatives** in addition to the\nannotations for potential assessment errors.\nFor example, for a user who successfully authenticated using\na 2-factor-authentication method and received a high reCAPTCHA score, you can\nannotate the assessment as `LEGITIMATE`. Alternatively, if reCAPTCHA\nscore was low and your site determined that the interaction was fraudulent or\nabusive, you can annotate the assessment as `FRAUDULENT`.\n\nThe following list shows additional information about some sample user\ninteractions that indicate whether a user interaction is legitimate or\nfraudulent:\n\n- Credit card chargebacks or other concrete evidence of fraud indicate that an earlier financial transaction was fraudulent.\n- A new account that sends messages that are flagged as spam by other users might indicate that the account creation was fraudulent.\n- A support case filed if a user has difficulty logging in to their account might indicate that the login attempt is legitimate.\n- A purchase or booking on a site that uses reCAPTCHA to defend against scraping might indicate that the user is legitimate.\n\nBefore you begin\n----------------\n\n- Ensure that you have the following Identity and Access Management role:\n reCAPTCHA Enterprise Agent (`roles/recaptchaenterprise.agent`).\n\n- Depending on where you have set up reCAPTCHA, complete the\n appropriate step:\n\n - [Create an assessment for your website](/recaptcha/docs/create-assessment-website).\n - [Create an assessment for your mobile application](/recaptcha/docs/create-assessment-mobile).\n - [Set up your WAF integration](/recaptcha/docs/setup-overview-waf).\n\nRetrieve the assessment ID\n--------------------------\n\nTo annotate an assessment, retrieve the unique assessment ID in the\nfollowing ways:\n\n- For web and mobile integrations, you can retrieve the unique assessment ID\n from the assessment response.\n\n After you create an assessment, you receive a JSON response as shown in the\n following example.\n\n Retrieve the unique assessment ID from the `name` field in the JSON response. \n\n ```bash\n {\n 'tokenProperties': {\n 'valid': True,\n 'hostname': 'www.google.com',\n 'action': 'homepage',\n 'createTime': u'2019-03-28T12:24:17.894Z'\n },\n 'riskAnalysis': {\n 'score': 0.1,\n 'reasons': ['AUTOMATION']\n },\n 'event': {\n 'token': 'RESPONSE_TOKEN',\n 'siteKey': 'KEY_ID'\n },\n 'name': 'ASSESSMENT_ID'\n }\n ```\n- For WAF integrations, you can retrieve the unique assessment ID from the\n reCAPTCHA token. The unique assessment ID is the\n unique alphanumeric string of 16 characters that appears at the end of the\n reCAPTCHA token after `:U=`. For example, if the reCAPTCHA token is\n `.................U=6ZZZZe73fZZZZZZ0`, then the assessment ID is `6ZZZZe73fZZZZZZ0`.\n\nAnnotate an assessment\n----------------------\n\n1.\n\n Determine the information and labels to add in the request JSON body\n depending on your use case.\n\n The following table lists the labels and values that you can use to annotate\n events:\n\n \u003cbr /\u003e\n\n2. Annotate an assessment using the\n [`projects.assessments.annotate`](/recaptcha/docs/reference/rest/v1/projects.assessments/annotate)\n method with the gcloud CLI or an API key.\n\n **Note:** If you are using the `v1beta1` version of the API, we recommend using the `v1` version because the new features, such as reCAPTCHA account defender are available only on `v1` version. For migrating from `v1beta1` to `v1`, see [Migrate from v1beta API to v1 API](/recaptcha/docs/migration-v1). \n\n ### gcloud CLI\n\n\n Before using any of the request data,\n make the following replacements:\n - \u003cvar translate=\"no\"\u003eASSESSMENT_ID\u003c/var\u003e: Value of the `name` field returned from the `projects.assessments.create` call.\n - \u003cvar translate=\"no\"\u003eANNOTATION_LABEL\u003c/var\u003e: The label to indicate whether the assessment is legitimate or fraudulent. Possible values are `LEGITIMATE` or `FRAUDULENT`.\n - \u003cvar translate=\"no\"\u003eANNOTATION_REASON\u003c/var\u003e: Describes the context for the annotation that was chosen for this assessment. To learn about possible values, see [reasons for annotating an assessment](https://cloud.google.com/recaptcha/docs/reference/rest/v1/projects.assessments/annotate#reason).\n\n\n HTTP method and URL:\n\n ```\n POST https://recaptchaenterprise.googleapis.com/v1/ASSESSMENT_ID:annotate\n ```\n\n\n Request JSON body:\n\n ```\n {\n \"annotation\": \"ANNOTATION_LABEL\"\n \"reasons\": \"ANNOTATION_REASON\"\n }\n ```\n\n To send your request, choose one of these options: \n\n #### curl\n\n | **Note:** The following command assumes that you have logged in to the `gcloud` CLI with your user account by running [`gcloud init`](/sdk/gcloud/reference/init) or [`gcloud auth login`](/sdk/gcloud/reference/auth/login) , or by using [Cloud Shell](/shell/docs), which automatically logs you into the `gcloud` CLI . You can check the currently active account by running [`gcloud auth list`](/sdk/gcloud/reference/auth/list).\n\n\n Save the request body in a file named `request.json`,\n and execute the following command:\n\n ```\n curl -X POST \\\n -H \"Authorization: Bearer $(gcloud auth print-access-token)\" \\\n -H \"Content-Type: application/json; charset=utf-8\" \\\n -d @request.json \\\n \"https://recaptchaenterprise.googleapis.com/v1/ASSESSMENT_ID:annotate\"\n ```\n\n #### PowerShell\n\n | **Note:** The following command assumes that you have logged in to the `gcloud` CLI with your user account by running [`gcloud init`](/sdk/gcloud/reference/init) or [`gcloud auth login`](/sdk/gcloud/reference/auth/login) . You can check the currently active account by running [`gcloud auth list`](/sdk/gcloud/reference/auth/list).\n\n\n Save the request body in a file named `request.json`,\n and execute the following command:\n\n ```\n $cred = gcloud auth print-access-token\n $headers = @{ \"Authorization\" = \"Bearer $cred\" }\n\n Invoke-WebRequest `\n -Method POST `\n -Headers $headers `\n -ContentType: \"application/json; charset=utf-8\" `\n -InFile request.json `\n -Uri \"https://recaptchaenterprise.googleapis.com/v1/ASSESSMENT_ID:annotate\" | Select-Object -Expand Content\n ```\n\n You should receive a successful status code (2xx) and an empty response.\n\n \u003cbr /\u003e\n\n ### API key\n\n\n Before using any of the request data,\n make the following replacements:\n - \u003cvar translate=\"no\"\u003eASSESSMENT_ID\u003c/var\u003e: Value of the `name` field returned from the `projects.assessments.create` call\n - \u003cvar translate=\"no\"\u003eANNOTATION_LABEL\u003c/var\u003e: The label to indicate whether the assessment is legitimate or fraudulent. Possible values are `LEGITIMATE` or `FRAUDULENT`.\n - \u003cvar translate=\"no\"\u003eANNOTATION_REASON\u003c/var\u003e: Describes the context for the annotation that was chosen for this assessment. To learn about possible values, see [reasons for annotating an assessment](https://cloud.google.com/recaptcha/docs/reference/rest/v1/projects.assessments/annotate#reason).\n\n\n HTTP method and URL:\n\n ```\n POST https://recaptchaenterprise.googleapis.com/v1/projects/PROJECT_ID/assessments/ASSESSMENT_ID:annotate?key=API_KEY\n ```\n\n\n Request JSON body:\n\n ```\n {\n \"annotation\": \"ANNOTATION_LABEL\"\n \"reasons\": \"ANNOTATION_REASON\"\n }\n ```\n\n To send your request, choose one of these options: \n\n #### curl\n\n | **Note:** Create an [API key](https://cloud.google.com/docs/authentication/api-keys#creating_an_api_key) to authenticate with the API.\n\n\n Save the request body in a file named `request.json`,\n and execute the following command:\n\n ```\n curl -X POST \\\n -H \"Content-Type: application/json; charset=utf-8\" \\\n -d @request.json \\\n \"https://recaptchaenterprise.googleapis.com/v1/projects/PROJECT_ID/assessments/ASSESSMENT_ID:annotate?key=API_KEY\"\n ```\n\n #### PowerShell\n\n | **Note:** Create an [API key](https://cloud.google.com/docs/authentication/api-keys#creating_an_api_key) to authenticate with the API.\n\n\n Save the request body in a file named `request.json`,\n and execute the following command:\n\n ```\n $headers = @{ }\n\n Invoke-WebRequest `\n -Method POST `\n -Headers $headers `\n -ContentType: \"application/json; charset=utf-8\" `\n -InFile request.json `\n -Uri \"https://recaptchaenterprise.googleapis.com/v1/projects/PROJECT_ID/assessments/ASSESSMENT_ID:annotate?key=API_KEY\" | Select-Object -Expand Content\n ```\n\n You should receive a successful status code (2xx) and an empty response.\n\n \u003cbr /\u003e\n\nWhat's next\n-----------\n\n- Learn about the [user accounts protection features of reCAPTCHA](/recaptcha/docs/protect-accounts-overview)."]]