Host.io API

Name: Host.io API
Brand: Host.io API
Availability: InStock

★ Only Publicly Available OpenAPI DocumentData EnrichmentCompany Databearer,basic,apiKey5 EndpointsREST

For Agents

Look up DNS, hosting, links, and backlinks for any domain, plus reverse-lookup all domains sharing an IP, NS, MX, or ASN.

Install Jentic One Beta

Connect the Host.io API to your agent

Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Host.io 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.

Step 1: Jentic One Host machine

# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh

Step 2: Agent machine

# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register       # connects your agent to your Jentic One instance

Jentic 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 Host.io API.

Resolve DNS records (A, NS, MX, TXT) for any domain in a single call

Fetch scraped website metadata including title, description, and tech stack hints

Pull outbound links from a domain's homepage for crawl mapping

GET STARTED

Start building with Host.io API

Explore with Jentic

View OpenAPI Document

Use Cases

Patterns agents use Host.io API for, with concrete tasks.

★ Phishing Domain Investigation

Investigate suspicious lookalike domains by pulling DNS, hosting, and reverse-lookup data from Host.io. The agent calls GET /full/{domain} for the suspect, then reverse-lookups its IP via GET /domains/{field}/{value} to find every other domain on the same host. Surfaces clusters of related phishing infrastructure quickly.

Call GET /full/{domain} for suspicious-bank-login.com, then GET /domains/ip/{ip} to list every domain sharing its IP.

Sales Prospecting Enrichment

Enrich an inbound lead's email domain with website metadata, hosting provider, and outbound link signals. The agent calls GET /web/{domain} for the title and description, GET /related/{domain} for related-domain counts, then formats the output for the CRM. Helps AEs qualify prospects before outreach.

Pull website metadata and DNS records for the prospect's domain and write a summary into the CRM lead record.

SEO Backlink Audit

Audit referring domains to a target site by calling GET /full/{domain}. The endpoint returns backlink counts and sample referring domains in one shot, so an agent can build a quick competitive backlink overview without scraping. Useful for SEO assistants and site migration audits.

Fetch GET /full/{domain} for the target site and emit the backlink count plus the top 10 referring domains.

AI Domain Intelligence Agent via Jentic

Plug Host.io into an AI security or research agent through Jentic so the agent can answer domain questions without juggling auth or building reverse-lookup logic. Jentic stores the API token in the MAXsystem vault and exposes each Host.io operation by intent search.

Search Jentic for 'list domains on same IP', load the schema, and execute against IP 1.2.3.4 to return all sharing domains.

Key Endpoints

5 endpoints — jentic publishes the only available openapi specification for host.

METHOD

PATH

DESCRIPTION

GET

/web/{domain}

Get scraped website metadata

GET

/dns/{domain}

Get DNS records (A, NS, MX, TXT)

GET

/related/{domain}

Get related-domain counts

GET

/full/{domain}

Get full domain report combining DNS, IP, links

GET

/domains/{field}/{value}

Reverse-lookup domains by IP, NS, MX, ASN, or backlink

GET

/web/{domain}

Get scraped website metadata

GET

/dns/{domain}

Get DNS records (A, NS, MX, TXT)

GET

/related/{domain}

Get related-domain counts

GET

/full/{domain}

Get full domain report combining DNS, IP, links

GET

/domains/{field}/{value}

Reverse-lookup domains by IP, NS, MX, ASN, or backlink

Why Jentic?

Three things that make agents converge on Jentic-routed access.

Credential isolation

Host.io credentials (bearer, basic, or query API key) are stored encrypted in the Jentic vault (MAXsystem). Agents receive scoped execution rights — raw credentials never enter the agent's context.

Intent-based discovery

Agents search by intent (e.g., 'reverse lookup domains by IP') and Jentic returns the matching Host.io operation with its path parameter shape ready to fill.

Time to first call

Direct integration: half a day across the three auth schemes and reverse-lookup parameters. Through Jentic: 15-30 minutes.

FAQs

Specific to using Host.io API through Jentic.

Why is there no official OpenAPI spec for Host.io API?

Host.io does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call Host.io API via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.

What authentication does the Host.io API use?

Three options are supported: bearer token (Authorization: Bearer <token>), HTTP basic, or an API key in the query string. Jentic stores the credential in the MAXsystem vault and injects whichever scheme the call requires.

Can I find every domain hosted on a given IP with the Host.io API?

Yes. GET /domains/{field}/{value} with field=ip and the IP address as the value returns the list of domains observed on that IP. The same path supports field=ns, mx, asn, and backlink for other reverse lookups.

What are the rate limits for the Host.io API?

Host.io rate limits are tied to plan tier — free plans are heavily throttled and paid plans scale up to thousands of requests per day. Check your plan in the Host.io dashboard and back off on 429 responses.

How do I look up DNS records for a domain with the Host.io API through Jentic?

Run pip install jentic, search for 'get DNS records for domain', load the GET /dns/{domain} schema, and execute. Jentic handles the auth header and returns the structured DNS payload.

Does the Host.io API give me both backlinks and outbound links?

Yes. The /full/{domain} endpoint returns scraped website metadata (title, description, outbound links sample) and backlink counts in a single response, so an agent can pull both link directions in one call.