Direct RPC IMPLEMENTED & VERIFIED

LinkedIn Voyager Client Service

Direct communication layer interfacing with LinkedIn's internal Voyager REST & GraphQL microservices without official developer APIs or browser automation. Implements normalized JSON parsing, automated CSRF handshakes, job discovery, Easy Apply onsite application submissions, and applicant status tracking.

Authentication & CSRF Handshake

LinkedIn's Voyager API enforces that all requests carry both the user's authenticated session ticket and a CSRF token derived from the active session.

Header / Cookie	Type	Example	Description
`li_at`	Cookie	`AQEDAT...`	Primary HTTP-only session authentication cookie.
`JSESSIONID`	Cookie	`"ajax:89237489234"`	Session identifier holding the CSRF challenge token.
`csrf-token`	Header	`ajax:89237489234`	Enforced Rule: Must match `JSESSIONID` with surrounding double quotes removed.
`x-restli-protocol-version`	Header	`2.0.0`	Restli 2.0 microservice protocol specification header.
`Accept`	Header	`application/vnd.linkedin.normalized+json+2.1`	Normalized entity graph format.

Internal Operations & Endpoints

GET /voyager/api/me

Validates active session credentials and extracts candidate profile entity URN.

curl 'https://www.linkedin.com/voyager/api/me' \
  -H 'csrf-token: ajax:89237489234' \
  -H 'x-restli-protocol-version: 2.0.0' \
  -H 'Cookie: li_at=AQEDAT...; JSESSIONID="ajax:89237489234"'

GET /voyager/api/search/hits?q=jobs&keywords={keywords}&location={location}

Executes direct Voyager job search with filters (remote, posted date, experience level).

POST /voyager/api/jobs/onsiteJobApplications

Direct RPC application submission for LinkedIn Easy Apply listings. Submits candidate responses, pre-uploaded resume URN, and contact information.

{
  "jobPostingUrn": "urn:li:fsd_jobPosting:3892839210",
  "responses": [
    { "questionUrn": "urn:li:fsd_question:101", "answer": { "stringAnswer": "Immediate" } },
    { "questionUrn": "urn:li:fsd_question:102", "answer": { "stringAnswer": "Yes" } }
  ],
  "contactDetail": {
    "emailAddress": "candidate@useme.ai",
    "phoneNumber": { "number": "+1234567890", "countryCode": "US" }
  },
  "resume": "urn:li:digitalMediaAsset:D560...9"
}

Resilience, Throttling & Checkpoint Guard

Checkpoint Detection: Automatically intercepts HTTP 403 or 999 responses with redirect targets containing /checkpoint/challenge/. Instantly halts automated jobs, marks connection as REQUIRES_AUTHORIZATION, and triggers Telegram alerts.
Humanized Cooldown: Enforces random jittered delays (30s – 90s) between submissions.
Bounded Retries: 3 attempts with exponential backoff on transient HTTP 429 and 503 errors.