CustomGPT.ai API
Official vendor OpenAPI document · agent-readyAI/MLLanguage Modelsbearer64 EndpointsREST
For Agents
Build and configure retrieval-augmented AI agents, ingest documents and sources, run grounded chat completions, and read conversations, citations, and analytics across 64 endpoints. Authenticates with a bearer token.
Use for: Create a new custom AI agent for a knowledge base, Add a document or website as a source for an agent, Send a message to an agent and get a grounded answer, List the conversations for an agent
Not supported: Does not train foundation models or provide general-purpose generation outside an agent's content. Use for building and running content-grounded CustomGPT.ai agents only.
The CustomGPT.ai API builds and operates retrieval-augmented AI agents grounded in your own content. Across 64 endpoints it creates and configures agents, ingests documents and data sources, runs chat completions in OpenAI format, manages conversations and citations, checks message trust scores, and returns traffic, query, and lead analytics.
Install Jentic One Beta
Connect the CustomGPT.ai API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the CustomGPT.ai 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%2Fcustomgpt.ai%2Fcustomgpt" | 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%2Fcustomgpt.ai%2Fcustomgpt" | 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 CustomGPT.ai API.
Create, configure, clone, and delete custom AI agents
Ingest documents and data sources and reindex or sync them
Run chat completions in OpenAI format grounded in your content
Manage conversations and export their messages
Retrieve citations and message trust scores for answers
Pull traffic, query, conversation, and lead analytics
Use Cases
Patterns agents use CustomGPT.ai API for, with concrete tasks.
★ Agent-Managed Knowledge Base Chatbots
An AI agent connected through Jentic can stand up and maintain a grounded chatbot without a human in the dashboard. It creates a CustomGPT.ai agent, adds documents and website sources, reindexes them, and then routes user questions to the agent's chat completion endpoint so answers stay tied to the ingested content.
Create an agent, add a set of documentation URLs as sources, reindex them, then send a user question and return the grounded answer
Grounded Answer Verification
When answers must be trustworthy, the source matters as much as the text. The CustomGPT.ai API returns citations, message claims, and a trust score for each answer and can verify a message's accuracy, so an agent can surface the supporting sources and hold back low-confidence responses.
Send a question to an agent, read the answer's trust score and citations, and only return the answer if the trust score is high enough
Conversation Analytics and Lead Export
Teams want to know what users ask and who engages. The CustomGPT.ai API reports traffic, query, and conversation analytics and exports captured leads, letting an agent compile a weekly summary of top questions and hand new leads to a CRM.
Pull the last week of query analytics for an agent and export any new leads it captured
Key Endpoints
64 endpoints — the customgpt.
METHOD
PATH
DESCRIPTION
POST
/api/v1/projects
Create an agent
POST
/api/v1/projects/{projectId}/sources
Add a data source to an agent
POST
/api/v1/projects/{projectId}/chat/completions
Send a message in OpenAI format
GET
/api/v1/projects/{projectId}/conversations
List conversations for an agent
GET
/api/v1/projects/{projectId}/reports/queries
Get query analytics for an agent
POST
/api/v1/projects
Create an agent
POST
/api/v1/projects/{projectId}/sources
Add a data source to an agent
POST
/api/v1/projects/{projectId}/chat/completions
Send a message in OpenAI format
GET
/api/v1/projects/{projectId}/conversations
List conversations for an agent
GET
/api/v1/projects/{projectId}/reports/queries
Get query analytics for an agent
Why Jentic?
What agents get from Jentic-routed access to this vendor.
Setup
Wiring CustomGPT.ai by hand means managing a bearer token and chaining agent creation, source ingestion, reindexing, and chat calls across 64 endpoints. Through Jentic you install once, import CustomGPT.ai from the API Directory, store the token once, and your agent calls the operations directly.
Permission scoping
Almost every operation addresses a project, page, or conversation by its ID in the URL path, so a rule can bound your agent to a single agent project as well as to specific operations. You might allow sending messages and reading citations while blocking agent and source deletion.
Credential isolation
Your CustomGPT.ai bearer token 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 'send a message to a CustomGPT agent', and Jentic returns the matching operation with its input schema so the agent calls it with the right project ID and message.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using CustomGPT.ai API through Jentic.
What authentication does the CustomGPT.ai API use?
The CustomGPT.ai API authenticates every request with a bearer token in the Authorization header, in JWT format per its OpenAPI spec. Through Jentic the token is stored once by your own self-hosted instance and injected when the agent calls, so it never appears in the agent's prompt or logs.
Is there a CustomGPT.ai MCP server?
You don't need an MCP server to give your agent the CustomGPT.ai API. Jentic connects it directly from the API Directory: import it, store your bearer token once, and your agent calls the agent, source, and chat operations. Operations are discovered on demand, so nothing extra loads into the agent's context.
Can I limit what my agent is allowed to do with the CustomGPT.ai API?
Yes. Almost every operation addresses a project, page, conversation, or other record by its ID in the URL path, so a rule can bound the agent to a single agent project as well as to specific operations. You might allow sending messages and reading citations while blocking agent and source deletion, with every call logged.
Does the CustomGPT.ai API support the OpenAI chat format?
Yes. The chat completions operation accepts requests in OpenAI format for a given agent, so an integration built for OpenAI chat completions can call a CustomGPT.ai agent whose answers stay grounded in your ingested content.
What are the rate limits for the CustomGPT.ai API?
The OpenAPI spec does not state fixed rate limits, though it exposes an account limits and usage endpoint you can query. Check the CustomGPT.ai documentation at https://docs.customgpt.ai for current limits before running high-volume ingestion or chat jobs.
How do I send a message to an agent through Jentic?
Search Jentic by intent, for example 'send a message to a CustomGPT agent', and Jentic returns the chat operation with its input schema. Your agent supplies the project ID and the message and reads back the grounded answer. To run it on your own infrastructure, install Jentic One from its GitHub repo.
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