canonical: https://jentic.com/apis/mailrambo.com/mailrambo

# MailRambo Verification API

The MailRambo Verification API answers a strict yes or no on whether an email address is deliverable, setting deliverable to true only for confirmed mailboxes and explaining every answer in a reason field. Single addresses are checked over GET or POST on the verify endpoint, either in full mode with a mailbox check or in a free fast mode for forms that covers syntax, typos, MX, disposable, and role checks. Larger lists go through batch jobs that you start and then poll by batch_id, and an account endpoint reports the plan and remaining credits.

## For AI agents

Check whether an email address is deliverable with a yes/no answer and reason, run batch verifications and poll their results, and read the remaining credit balance.

## Scope

Does not handle sending email, inbox placement testing, or contact enrichment with phone or company data. Use for verifying email address deliverability only.

## Capabilities

- Get a strict yes/no deliverable answer with a reason for one address through GET or POST `/v1/verify`
- Run a free sub-second check for sign-up forms with mode=fast, covering syntax, typos, MX, disposable, and role addresses
- Request the full detail block with detail=full to see a grade, score, inbox_provider, flags such as catch_all and mailbox_exists, and DNS records like SPF and DMARC
- Start a batch verification of a named email list of up to 200 addresses with POST `/v1/verify/batch`, using an Idempotency-Key header so retries do not charge twice
- Poll a batch by batch_id for its status, progress, and per-address deliverable results
- Read the plan, credits_remaining, and period_end for the key's owner from GET `/v1/account`

## Use cases

### Agent-run deliverability checks through Jentic

An agent that adds contacts to a mailing tool first asks MailRambo whether each address is deliverable and keeps only the ones that come back true, logging the reason for the rest. Through Jentic the agent finds the verify operation by intent, the mr_live_ key stays in the developer's own Jentic One instance, and a rule can hold the agent to verification and account reads.

Example prompt: Call GET `/v1/verify` with email 'jane@example.com' and add the contact only if deliverable is true, otherwise record the reason

### Batch list verification

To clean a whole list, POST `/v1/verify/batch` with the emails array and an optional name starts a job charged at one credit per address up front, and sending an Idempotency-Key makes a retried request replay the first response rather than charge again. GET `/v1/verify/batch/{batch_id}` then reports status and progress and returns one yes/no result per address when the job completes.

Example prompt: POST `/v1/verify/batch` with emails from the leads list and name 'November leads' and an Idempotency-Key header, then poll GET `/v1/verify/batch/{batch_id}` until the results appear

### Free sign-up form checks with mode=fast

Sign-up forms need a quick answer. Calling the verify endpoint with mode=fast runs a free sub-second check for syntax, typos, MX, disposable, and role addresses, so the form can reject throwaway or mistyped addresses and offer the suggestion field, then run a full check later when a mailbox answer matters.

Example prompt: Call GET `/v1/verify` with email 'user@gmial.com' and mode 'fast', then show the suggestion value to the user if one is returned

## Key endpoints

| Method | Path | Description |
| --- | --- | --- |
| GET | `/v1/verify` | Verify one email address |
| POST | `/v1/verify` | Verify one email address with a JSON body |
| POST | `/v1/verify/batch` | Start a batch verification |
| GET | `/v1/verify/batch/{batch_id}` | Poll a batch for results |
| GET | `/v1/account` | Read plan and remaining credits |

## Key resources

- **Verifications** — Single-address results with email, deliverable, reason, suggestion, mode, cached, and an optional detail block
- **Batches** — Batch jobs identified by batch_id with status, progress, total, checked, and per-address results
- **Account** — Plan, credits_remaining, credits_total, pack_credits, and period_end for the key's owner

## AI readiness

This API is usable in Jentic One now. Its AI-readiness score against Jentic's framework shows where it stands today and where improvements would make it even easier for agents to use.

- **Score:** 64 / 100
- **Maturity:** AI-Aware
- **Dimensions:**
  - Foundational Compliance: 93 / 100
  - Developer Experience & Jentic Compatibility: 69 / 100
  - AI-Readiness & Agent Experience: 43 / 100
  - Agent Usability: 94 / 100
  - Security: 60 / 100
  - AI Discoverability: 58 / 100
- **View full report:** https://jentic.com/apis/mailrambo.com/mailrambo/scorecard
- **How the score is calculated:** https://docs.jentic.com/reference/api-readiness-framework/overview/
- **More about the dimensions:** https://docs.jentic.com/reference/api-readiness-framework/specification/#dimensional-model-overview

### Score it yourself

Every API in the directory is allowlisted, so you can re-score it with no key required.

- **Score your own API:** https://jentic.com/scorecard.md
- **Scoring CLI agent skill:** https://github.com/jentic/jentic-api-scorecard/blob/main/skills/jentic-api-scorecard/SKILL.md

```sh
npx @jentic/api-scorecard-cli score <openapi-url>
```

## Why Jentic

- **Setup:** Wiring MailRambo by hand means passing its bearer key, choosing between mr_live_ and mr_test_ keys, and handling batch polling and idempotent retries yourself. Through Jentic you install once, import MailRambo from the API Directory, store the key once, and your agent calls it.
- **Permission scoping:** MailRambo puts the batch_id in the URL path when polling, so a rule can pin your agent to one batch's results, while single verifications carry the address in the query or body and are bounded by operation. You choose the operations it may call, so credit-spending batch creation is not included unless you add it.
- **Credential handling:** Your MailRambo API key is stored once, encrypted, by your own Jentic One instance and injected at execution time. It never enters the agent's prompt, logs, or context.
- **Discovery method:** Agents search Jentic by intent such as 'check if an email is deliverable' or 'verify a list of emails', and Jentic returns the matching MailRambo operation with its input schema so the agent calls the right endpoint without browsing the reference docs.

## Related APIs

- **NeverBounce API** — Email verification service with single checks and bulk list jobs
- **Kickbox Email Verification API** — Email verification API with deliverability results per address
- **MailerSend API** — Transactional email sending API

## FAQ

### Is there a MailRambo MCP server?

You don't need an MCP server to give your agent MailRambo. Jentic connects it directly from the API Directory: import it, store your API key once, and your agent calls it. Operations are discovered on demand, so no extra tool definitions sit in the agent's context.

### What authentication does the MailRambo Verification API use?

Per its OpenAPI spec, the MailRambo Verification API uses bearer authentication: send your API key in the Authorization header. Keys come in two forms, mr_live_ for real verifications and mr_test_ for integrating without spending credits. Through Jentic the key is stored encrypted by your own Jentic One instance and injected at execution time, so it never enters the agent's context.

### Can I limit what my agent is allowed to do with MailRambo?

Yes. For example, write a rule that allows GET `/v1/verify` and GET `/v1/account` but not POST `/v1/verify/batch`, so the agent can check single addresses and read the balance without starting credit-spending batch jobs. Every call it makes is logged on your own machine.

### How much does a MailRambo verification cost?

Per the spec, a full verification costs one credit per address. It is free when the address is syntactically invalid, when it repeats a check from the last 24 hours, or when you use mode=fast. Batch jobs charge one credit per address up front, and reading GET `/v1/account` is free.

### How do I verify a list of emails through Jentic?

Install Jentic One, import the MailRambo Verification API from the directory, and search for 'verify a batch of email addresses'. Jentic returns the batch create operation with its input schema; your agent sends the emails array, stores the returned batch_id, and polls the batch status operation until results appear. To run it on your own infrastructure, install Jentic One from its GitHub repo.

### What are the rate limits for the MailRambo Verification API?

The OpenAPI spec does not specify rate limits. Check the MailRambo documentation at https://www.mailrambo.com for current limits.