Monitoring

Custom Request Headers

Send custom HTTP headers with every check — bearer tokens, User-Agents, host overrides. Validated as JSON, 4 kB cap.

Updated 2026-06-15

2 min read

headers

authentication

bearer

Custom Request Headers#

Send extra HTTP headers with every check so LemWatch can reach endpoints that need authentication, a specific User-Agent, or a host override.

A JSON object — keys are header names, values are strings.

{
  "Authorization": "Bearer eyJhbGciOi...",
  "User-Agent": "LemWatch-Probe/1.0",
  "X-Forwarded-Host": "api.example.com"
}

Must be valid JSON parsable as an object (not an array, not a bare string)

Max 4,000 characters total

Header names and values are sent verbatim — no escaping applied

Empty string "" is treated as "no custom headers"

Protect a staging environment

{ "Authorization": "Basic dXNlcjpwYXNz" }

Allowlist past your WAF

{ "X-LemWatch-Probe": "your-shared-secret" }

Pin a CDN edge

{ "Host": "origin.example.com" }

Headers are stored encrypted at rest. They are visible in the audit log to admins of your organization. Rotate any token if a teammate leaves.

"Custom headers must be a valid JSON object" — your value is missing braces, has a trailing comma, or is an array

Auth header ignored — confirm the upstream actually accepts the header name (some WAFs strip Authorization)

Headers gone after save — make sure you're on the latest build; older releases dropped this field due to a Zod schema gap

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