Instantly API
67
AI ReadinessAI-Aware (B)67/100
Agent-ready OpenAPI document · curated by JenticMarketingMarketing AutomationapiKey26 EndpointsREST
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For Agents
Manage Instantly cold-email accounts, campaigns, and leads - pause and resume sender accounts, run campaigns, and import leads programmatically.
Use for: I want to create a new Instantly cold-email campaign, Pause sending on an Instantly account that is showing deliverability issues, Import a CSV of leads into an existing Instantly campaign, Resume warm-up on an Instantly account after it cooled down
Not supported: Does not handle SMS, transactional email, or CRM contact records - use for cold-email account, campaign, and lead management only.
Jentic publishes the only available OpenAPI specification for Instantly API, keeping it validated and agent-ready. The Instantly v2 API gives outbound sales and growth teams programmatic control over cold-email infrastructure, including sender accounts, campaigns, leads, and email sends. Across 26 endpoints, the API covers account warm-up pause and resume, campaign creation, lead import, and reply tracking, so an automation can keep multi-account outbound running without UI clicks. Authentication is a single API key passed in the Authorization header, which makes embedding the API into existing workflows straightforward.
Install Jentic One Beta
Connect the Instantly API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Instantly 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%2Finstantly.ai%2Finstantly" | 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%2Finstantly.ai%2Finstantly" | 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 Instantly API.
Provision and configure Instantly sender accounts via POST /accounts and PATCH /accounts/{id}
Pause and resume warm-up or sending on individual accounts via /accounts/{id}/pause and /accounts/{id}/resume
Create outbound campaigns and update their step sequences via /campaigns
Import and update leads attached to campaigns through the /leads endpoints
Read sent and received emails to drive reply-handling automations through /emails
Remove or archive accounts that have been deprecated for sending
Use Cases
Patterns agents use Instantly API for, with concrete tasks.
★ Account Health Auto-Pause
Listen to deliverability signals from an external monitor and call POST /accounts/{id}/pause when bounce or spam-complaint thresholds are exceeded, then POST /accounts/{id}/resume once the account recovers. This prevents domain reputation damage without requiring an operator to log into the Instantly dashboard, and the small endpoint surface makes the integration achievable in a few hours.
When monitor flags an account, POST /accounts/{id}/pause; when health recovers, POST /accounts/{id}/resume.
Lead Import from CRM to Campaign
When a CRM tags a contact as 'outbound-ready', push the contact into the matching Instantly campaign via the /leads endpoints with full custom variables for personalisation. The integration removes the manual CSV upload step and keeps the campaign seeded with fresh leads as soon as they qualify in the CRM.
For each CRM contact tagged 'outbound-ready', call the Instantly create-lead operation with the campaign id, email, and merge fields.
Reply Routing into a Helpdesk
Poll /emails for inbound replies to outbound campaigns, classify intent, and forward qualified replies into a sales inbox or helpdesk. This avoids the trap of replies sitting unread in a sender mailbox by routing them to the system where reps actually work.
List Instantly emails received in the last hour, filter to replies, and create a corresponding helpdesk ticket for each one.
AI Agent Outbound Operator via Jentic
An AI agent given access to Instantly through Jentic can spin up a campaign, attach leads, and respond to deliverability alerts on its own. Jentic exposes each Instantly v2 operation by intent and isolates the API key in its vault, so the agent makes structured calls without seeing the credential.
Through Jentic, call instantly_create_campaign with a name and step sequence, then instantly_add_leads to attach a list of prospects to the new campaign.
Key Endpoints
26 endpoints — jentic publishes the only available openapi specification for instantly api, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
POST
/accounts
Create a sender account
GET
/accounts
List sender accounts
POST
/accounts/{id}/pause
Pause an account
POST
/accounts/{id}/resume
Resume an account
POST
/campaigns
Create an outbound campaign
POST
/accounts
Create a sender account
GET
/accounts
List sender accounts
POST
/accounts/{id}/pause
Pause an account
POST
/accounts/{id}/resume
Resume an account
POST
/campaigns
Create an outbound campaign
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.
I
Instantly API
- AI-Aware (B)67/100
75
Foundational Compliance63
Developer Experience & Jentic Compatibility54
AI-Readiness & Agent Experience94
Agent Usability50
Security100
AI DiscoverabilityPowered by JenticScoring Framework 1.0.0 | Scoring Engine 0.4.0
Show dimension breakdown
75
Foundational Compliance
Base layer of spec validity and structural soundness.
Grade: A-Signals: 4
98%
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).
2%
Structural Integrity
Structural correctness score based on schema issues using logarithmic dampening.
63
Developer Experience & Jentic Compatibility
Clarity, completeness, and ingestion readiness for developers and tooling.
Grade: B-Signals: 4
0%
Example Density
How richly the API is illustrated with examples.
100%
Example Validity
Percentage of examples that conform to their schemas.
50%
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.
54
AI-Readiness & Agent Experience
Semantic breadth, depth, and agent comprehension for AI systems.
Grade: CSignals: 4
55%
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.
60%
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.
50
Security
Trust, risk posture, and security compliance.
Grade: C-Signals: 1
50%
Authentication Strength
Average quality of security schemes based on authentication method strength (weakest link for OAuth2).
100
AI Discoverability
Findability, semantic richness, and reasoning readiness.
Grade: A+Signals: 1
100%
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 the Instantly v2 API by hand means setting up its header API key auth, tracking the /api/v2 base path, and handling account pause and resume flows yourself. Through Jentic you install once, import the Instantly API from the API Directory, store the API key once, and your agent calls it.
Permission scoping
Instantly puts the account id in the URL path (/accounts/{id}/pause, /accounts/{id}/resume), so a rule can pin your agent to one account and the campaign and lead operations you approve. You choose the operations it may call, so account creation is not included unless you add it.
Credential isolation
Your Instantly API key is stored once, encrypted, by your own Jentic One instance and injected into the Authorization header at execution time. It never enters the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'pause an Instantly account' or 'create an Instantly campaign', and Jentic returns the matching v2 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 Instantly API through Jentic.
Why is there no official OpenAPI spec for Instantly API?
Instantly does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call Instantly API via structured tooling. It is validated against the live API and kept up to date. Get started with Jentic One, the self-hosted execution layer.
What authentication does the Instantly API use?
The Instantly API uses an API key sent in the Authorization header (the apiKey scheme is named 'apiKey' and bound to the Authorization header). Through Jentic, the API key sits in your encrypted Jentic One instance and is injected into the request at execution time.
Can I pause and resume sender accounts with the API?
Yes. POST /accounts/{id}/pause stops sending and warm-up on a given account; POST /accounts/{id}/resume re-enables it. This is the recommended way to react to deliverability alerts without operator intervention.
What are the rate limits for the Instantly API?
The OpenAPI specification does not encode explicit rate limits. Treat each endpoint as a single-record operation, batch lead imports rather than firing one request per lead where possible, and back off on 429 responses returned by the gateway.
How do I create a campaign through Jentic?
Install with pip install jentic, then run the search-load-execute flow with the query 'create an Instantly campaign'. Jentic returns the operation backed by POST /campaigns; the agent supplies the campaign name, schedule, and step sequence and receives the new campaign id.
Can I read replies to my outbound campaigns?
Yes. The /emails endpoints expose sent and received messages for the connected accounts, so an automation can list inbound mail, filter to replies on a specific campaign, and forward them into a CRM or helpdesk.
Can I limit what my agent is allowed to do with the Instantly API?
Yes. Because you run Jentic One yourself, your own rules decide which Instantly operations and credentials the agent may call. Since Instantly puts the account id in the URL path for calls like POST /accounts/{id}/pause and POST /accounts/{id}/resume, you can pin the agent to a single account and to only the campaign and lead operations you approve. Account creation is excluded unless you explicitly add it, so the agent never reaches operations you have not granted.
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