canonical: https://jentic.com/apis/mailprobe.dev/mailprobe

# MailProbe API

The MailProbe API verifies email addresses in real time, checking syntax, the DNS MX lookup, and a live SMTP handshake for each address without caching any result. One call to the verify endpoint takes 1 to 20 addresses and returns, in input order, a raw result, an actionable status, a deterministic 0-100 score, and flags such as catch_all, disposable, role_based, and did_you_mean. The service is hosted in the EU and charges one credit per address actually probed, with a second endpoint to read the remaining credit balance.

## For AI agents

Verify up to 20 email addresses per call with a live SMTP probe, getting a status, score, and reason for each, and check the remaining credit balance.

## Scope

Does not handle sending email, hosting mailboxes, or enriching contacts with phone or company data. Use for verifying email address deliverability only.

## Capabilities

- Verify 1 to 20 email addresses in one synchronous call to POST `/api/v1/verify`, with results returned in input order
- Read an actionable status for each address (valid, risky, invalid, or unknown) alongside the raw SMTP result such as deliverable or catch-all
- Rank addresses by a deterministic 0-100 score instead of discarding every risky mailbox
- Spot disposable, role-based, and free-provider addresses and catch typos through the did_you_mean suggestion
- Cap how long a verification waits with the timeout body field (5 to 95 seconds) so slow mail servers do not stall a sign-up flow
- Check the remaining credit balance with GET `/api/v1/credits` before a large verification run

## Use cases

### Agent-run email list cleaning through Jentic

An agent preparing an outreach list sends the addresses to MailProbe in groups of up to 20 and drops those whose status comes back invalid, while scoring risky ones instead of discarding them. Through Jentic the agent finds the verify operation by intent, the mp_live_ key stays in the developer's own Jentic One instance, and a rule can keep the agent on verification and balance checks.

Example prompt: Call GET `/api/v1/credits` to confirm the balance, then POST `/api/v1/verify` with emails ['ana@example.com', 'sales@example.org'] and keep only results whose status is 'valid'

### Sign-up form validation with a time budget

A sign-up form cannot wait for a slow mail server. Setting the timeout field to 25 makes POST `/api/v1/verify` answer within that window; any address without a verdict returns unknown with reason timeout at no charge, so the form can accept the user and re-check later. The did_you_mean field lets the form suggest a fix for a typo such as gmial.com.

Example prompt: POST `/api/v1/verify` with emails ['noreply@gmial.com'] and timeout 25, then show the did_you_mean value if one is returned

### Lead quality screening

Before importing leads into a CRM, each address can be checked for disposable, role_based, and free_provider flags along with the catch_all indicator. Combining those flags with the 0-100 score lets a sales team route clean business addresses straight in and hold the rest for review.

Example prompt: POST `/api/v1/verify` with a list of 15 lead emails and flag every result where disposable or role_based is true or score is below 50

## Key endpoints

| Method | Path | Description |
| --- | --- | --- |
| POST | `/api/v1/verify` | Verify 1 to 20 email addresses |
| GET | `/api/v1/credits` | Check the credit balance |

## Key resources

- **Verification results** — Per-address result, status, score, reason, retry_after, SMTP codes, and flags such as catch_all, disposable, and role_based
- **Credits** — The account's remaining credit balance, with one credit charged per address actually probed

## 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:** 75 / 100
- **Maturity:** AI-Aware
- **Dimensions:**
  - Foundational Compliance: 94 / 100
  - Developer Experience & Jentic Compatibility: 78 / 100
  - AI-Readiness & Agent Experience: 60 / 100
  - Agent Usability: 94 / 100
  - Security: 60 / 100
  - AI Discoverability: 81 / 100
- **View full report:** https://jentic.com/apis/mailprobe.dev/mailprobe/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 MailProbe by hand means passing its mp_live_ bearer key, respecting the per-key and per-IP request limits, and handling Retry-After on 429 responses yourself. Through Jentic you install once, import MailProbe from the API Directory, store the key once, and your agent calls it.
- **Permission scoping:** MailProbe carries the addresses inside the request body and has no resource ids in its paths, so limit the agent to the operations it needs, such as verifying addresses and reading the credit balance. Rules bound which operations your agent may call, not which addresses it submits.
- **Credential handling:** Your MailProbe 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 'verify an email address' or 'check email credits', and Jentic returns the matching MailProbe 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 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 MailProbe MCP server?

You don't need an MCP server to give your agent MailProbe. 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 MailProbe API use?

Per its OpenAPI spec, the MailProbe API uses bearer authentication: send your mp_live_ API key, created from the MailProbe dashboard, in the Authorization header as Bearer mp_live_.... 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 MailProbe?

Yes. For example, write a rule that allows only GET `/api/v1/credits`, so the agent can report the balance but cannot spend credits on probes until you add POST `/api/v1/verify.` The addresses travel in the request body, so rules bound which operations the agent calls, not which addresses it submits.

### What are the rate limits for the MailProbe API?

The MailProbe OpenAPI spec states a limit of 60 requests per minute per API key and 300 requests per minute per IP address across all keys. The limits count requests, not addresses, so a 20-address batch counts as one request. A 429 response carries a Retry-After header with the seconds to wait.

### How many addresses can I verify in one call?

POST `/api/v1/verify` accepts between 1 and 20 addresses in the emails array. Duplicates, syntactically invalid entries, and non-string entries cost nothing, and longer lists belong in the dashboard batch screen.

### How do I verify an email address through Jentic?

Install Jentic One, import the MailProbe API from the directory, and search for 'verify an email address'. Jentic returns the verifyEmails operation with its input schema, and your agent sends the emails array with an optional timeout. To run it on your own infrastructure, install Jentic One from its GitHub repo.

### Does MailProbe store verification results?

No. According to its spec, every address is probed live and no verification result is cached or stored, so each request re-probes and costs one credit per address actually probed.