MailProbe API
75
AI ReadinessAI-Aware (A-)75/100
Official vendor OpenAPI document · agent-readyData EnrichmentContact Enrichmentbearer2 EndpointsREST
For 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.
Use for: Check whether this email address is deliverable before I add it to the list, Verify a batch of 20 sign-up emails in one call, Find all disposable addresses in a lead list, I want to know my remaining MailProbe credits
Not supported: Does not handle sending email, hosting mailboxes, or enriching contacts with phone or company data. Use for verifying email address deliverability only.
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.
Install Jentic One Beta
Connect the MailProbe API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the MailProbe API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
1
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fmailprobe.dev%2Fmailprobe" | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fmailprobe.dev%2Fmailprobe" | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with MailProbe API.
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
Patterns agents use MailProbe API for, with concrete tasks.
★ 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.
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.
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.
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
2 endpoints — 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.
METHOD
PATH
DESCRIPTION
POST
/api/v1/verify
Verify 1 to 20 email addresses
GET
/api/v1/credits
Check the credit balance
POST
/api/v1/verify
Verify 1 to 20 email addresses
GET
/api/v1/credits
Check the credit balance
Jentic AI Readiness Score
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.
M
MailProbe API
- AI-Aware (A-)75/100
94
Foundational Compliance78
Developer Experience & Jentic Compatibility60
AI-Readiness & Agent Experience94
Agent Usability60
Security81
AI DiscoverabilityPowered by JenticScoring Framework 1.0.0 | Scoring Engine 0.4.2
Show dimension breakdown
94
Foundational Compliance
Base layer of spec validity and structural soundness.
Grade: A+Signals: 4
99%
Lint Results
Aggregated quality score from linter diagnostics, weighted by severity.
100%
Resolution Completeness
Percentage of `$ref` references that resolve successfully.
100%
Specification Validity
Checks whether the API description parses successfully and conforms to its declared specification (e.g., OpenAPI).
75%
Structural Integrity
Structural correctness score based on schema issues using logarithmic dampening.
78
Developer Experience & Jentic Compatibility
Clarity, completeness, and ingestion readiness for developers and tooling.
Grade: A-Signals: 4
50%
Example Density
How richly the API is illustrated with examples.
100%
Example Validity
Percentage of examples that conform to their schemas.
62%
Response Coverage
Percentage of operations with complete response definitions (success, client error, server error).
100%
Tooling Readiness
Health of API ingestion, bundling, and resolution within Jentic pipelines.
60
AI-Readiness & Agent Experience
Semantic breadth, depth, and agent comprehension for AI systems.
Grade: C+Signals: 4
68%
Description Coverage
Coverage of descriptions across API elements.
0%
Error Standardization
Coverage of RFC 9457 Problem Details for error responses.
100%
OperationId Quality
Coverage, uniqueness, and casing consistency of operationIds for AI inference.
71%
Summary Coverage
Coverage of summaries across operations/tags/info.
94
Agent Usability
Functional utility, complexity comfort, and AI orchestration readiness.
Grade: A+Signals: 1
94%
Complexity Comfort
Agent comfort level based on API operational and structural complexity.
60
Security
Trust, risk posture, and security compliance.
Grade: B-Signals: 1
60%
Authentication Strength
Average quality of security schemes based on authentication method strength (weakest link for OAuth2).
81
AI Discoverability
Findability, semantic richness, and reasoning readiness.
Grade: ASignals: 1
81%
Descriptive Richness
Clarity and depth of descriptions across API elements.
Score it yourself
Every API in the directory is allowlisted, so you can re-score it with no key required.
npx @jentic/api-scorecard-cli score <openapi-url>Why Jentic?
What agents get from Jentic-routed access to this vendor.
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 isolation
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.
Intent-based discovery
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
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using MailProbe API through Jentic.
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.
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