> ## Documentation Index > Fetch the complete documentation index at: https://docs.outreign.io/llms.txt > Use this file to discover all available pages before exploring further. # Check email deliverability > Same verifier as app search/enrichment, not signup validation. No reveal credit charged. Limit 10 checks/minute and a rolling daily allowance equal to plan daily search cap (100/250/500/1500); shared by API/MCP. Sends nothing. verified=true only for valid; invalid=false; catch_all, role and unknown=null. Not a delivery guarantee. ## OpenAPI ````yaml /public/openapi.json post /email/verify openapi: 3.1.0 info: title: OutReign API version: 1.2.0 summary: B2B lead intelligence and outbound sales API description: >- The OutReign REST API lets your server read and manage the data in an OutReign account: saved leads, pipeline deals, activities and contacts. It can also enrich and score saved leads and generate AI email drafts. **Base URL:** `https://api.outreign.io/rest-api` **Authentication:** send your key in the `X-API-Key` header. Create keys in OutReign under Settings → API Keys. API access is included on Starter and above. **Format:** JSON request and response bodies, UTF-8. Single records are returned in `data`; lists return `data`, `count`, `limit` and `offset`. Errors return `error` with a message. **Scope:** Fresh B2B prospect search, company search, person lookup, email verification and saved-lead research use the same app handlers and account restrictions. Nothing is automatically saved or sent by discovery. See https://docs.outreign.io/developer-docs/capabilities. MCP (for AI assistants) and webhooks are documented at https://docs.outreign.io. contact: name: OutReign support email: support@bdotindustries.com url: https://outreign.io/connect termsOfService: https://outreign.io/terms servers: - url: https://api.outreign.io/rest-api description: Production security: - ApiKeyAuth: [] tags: - name: Leads description: >- Saved leads: the people and companies you prospect. Enrichment adds verified contact and company data; scoring rates fit and intent against your ICP. - name: Deals description: Pipeline opportunities, optionally linked to a saved lead. - name: Activities description: Tasks, calls, meetings and notes linked to a lead or deal. - name: Contacts description: People records in your contact database, separate from saved leads. - name: Outreach description: >- AI email drafts for a lead. Full-email drafts are returned and saved to Outreach Studio and Unified Inbox; nothing is sent. - name: Prospecting description: Real app discovery and verification with account limits. externalDocs: description: Human API documentation url: https://docs.outreign.io paths: /email/verify: post: tags: - Prospecting summary: Check email deliverability description: >- Same verifier as app search/enrichment, not signup validation. No reveal credit charged. Limit 10 checks/minute and a rolling daily allowance equal to plan daily search cap (100/250/500/1500); shared by API/MCP. Sends nothing. verified=true only for valid; invalid=false; catch_all, role and unknown=null. Not a delivery guarantee. operationId: verifyEmail requestBody: required: true content: application/json: schema: type: object additionalProperties: false properties: email: type: string minLength: 1 maxLength: 320 required: - email example: email: jordan@northwind.io responses: '200': description: >- App action result. Check error/error_code even on HTTP 200. Examples are illustrative, not actual customer results. content: application/json: schema: type: object properties: email: type: string status: type: string enum: - valid - invalid - catch_all - role - unknown verified: type: - boolean - 'null' reason: type: string cached: type: boolean credits_charged: type: integer const: 0 error: type: string example: email: invalid-address status: invalid verified: false reason: Invalid email format cached: false credits_charged: 0 '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '429': $ref: '#/components/responses/RateLimited' '500': $ref: '#/components/responses/ServerError' components: responses: BadRequest: description: The body is not valid JSON or a required field is missing. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: contact_name and company_name are required Unauthorized: description: >- The `X-API-Key` header is missing, or the key is invalid, inactive or expired. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: Invalid API key Forbidden: description: >- Your plan does not include API access, or the daily allowance is used up. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: >- API access is included on Starter and above. Upgrade your plan to use the API. headers: X-RateLimit-Remaining: $ref: '#/components/headers/X-RateLimit-Remaining' X-RateLimit-Reset: $ref: '#/components/headers/X-RateLimit-Reset' RateLimited: description: Too many requests. Wait until `resetAt` before retrying. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: Rate limit exceeded resetAt: '2026-11-06T06:01:00.000Z' headers: X-RateLimit-Remaining: $ref: '#/components/headers/X-RateLimit-Remaining' X-RateLimit-Reset: $ref: '#/components/headers/X-RateLimit-Reset' ServerError: description: >- Unexpected failure. Retry reads with backoff; read a record back before retrying a write. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: Internal server error schemas: Error: type: object required: - error description: Error body returned with every non-2xx status. properties: error: type: string description: Human-readable explanation. Safe to log; never contains your key. resetAt: type: string format: date-time description: 'Present on rate-limit errors: when you can retry.' available: type: array items: type: string description: 'Present on unknown-resource errors: the valid resources.' headers: X-RateLimit-Remaining: description: >- Requests left in the current per-minute window for this key and resource. schema: type: string example: '28' X-RateLimit-Reset: description: ISO 8601 time when the window refills. schema: type: string format: date-time example: '2026-11-06T06:01:00.000Z' securitySchemes: ApiKeyAuth: type: apiKey in: header name: X-API-Key description: >- Your secret API key. Create it in OutReign → Settings → API Keys and send it on every request as `X-API-Key: `. The key acts as its owner: every request reads and writes that owner's data. Keep it server-side; never ship it in browser or mobile code. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.