The service at a glance
Custom ChatGPT integrations, built by Softflow.
Softflow develops ChatGPT plugins and custom GPT Actions for software products and business workflows. I’m Lukáš Jursa, your developer and direct contact. Delivery can cover the API connection, MCP tools or Actions schema, authentication, tests, deployment and documentation.
- Best starting point
- One user task, a system owner and access to an existing API.
- First decision
- Check the intended ChatGPT environment and agree a testable pilot.
- Pricing
- Written proposal after scope review. Any paid discovery is agreed before it starts.
- After delivery
- Agreed source code and handover; hosting, API usage and maintenance are scoped separately.
Download the project brief template or check what your project needs.
01 / A useful entry point to your product
Start with a task your customers already need to finish.
Your product may already hold the data and business rules. A ChatGPT integration gives users another way to reach them: asking for a record, comparing options or preparing the next step without navigating several screens.
Find and compare
Search a catalogue, query live availability or retrieve relevant account information. Return results with enough context for the user to make a decision.
Prepare and act
Draft a quote, create a support request or update an allowed field. Validate the request and define where a person must confirm a change.
Connect a team workflow
Look up a CRM record, summarise a project status or prepare a report from an existing system. Keep access tied to the signed-in user's permissions.
Choose a use case that fits your product and can be tested against a clear result. We can start with one of these workflows or review the task your users already ask for.
02 / Choose the right integration
ChatGPT plugins, MCP servers and custom GPT Actions
People use “ChatGPT app development” and “plugin development” for related services. Current OpenAI plugin documentation describes plugins that combine skills, MCP servers and optional interfaces. If you are looking for Apps SDK development, we will map that requirement to the current plugin architecture before choosing the implementation.
Bring your service into ChatGPT
For a product experience with well-defined tools, reusable instructions and, when useful, an interactive interface. I scope the MCP server, API connections, authentication and plugin packaging together.
Connect a custom GPT to your API
For a focused assistant that retrieves data or performs operations through a REST API. I develop the OpenAPI schema, configure authentication and test the actions with realistic requests.
You do not need to select the technology first. Tell me who will use the integration and what they should accomplish. I will recommend a route based on the workflow, your existing API and the intended distribution.
03 / Clear scope, tangible delivery
What you receive
- A scoped first version. The user journey, tools, permitted actions and acceptance criteria agreed before implementation.
- A working integration. The agreed MCP server and plugin package, or custom GPT Actions with their schema and backend connections.
- Access controls. Authentication appropriate to your service, server-side permission checks and explicit boundaries for write operations.
- Tests for real conditions. Normal requests, ambiguous inputs, missing access, empty results, duplicate submissions and upstream failures.
- Deployment and handover. Source code, configuration instructions, environment requirements and an operations guide within the agreed scope.
- A release plan. Test prompts, known limitations and submission preparation if public distribution is part of the engagement.
You receive the agreed project code and documentation. Hosting, service accounts and ongoing support responsibilities are defined in the proposal so the integration can be maintained after launch.
A concrete first release
Example pilot: catalogue search and a draft quote
Imagine a product with an existing catalogue API. A user asks for suitable items, checks the options and prepares a quote. The initial scope could include three tools: search products, retrieve one product and prepare a draft quote. This is a sample scope for discussion, not a claim about a delivered client project.
Read-only pilot
One data source and a narrow search or lookup task. Agree the inputs, access boundary and expected result before adding write operations.
Authenticated workflow
Account linking, user permissions and an agreed draft or write action. Include permission-denied cases and duplicate-operation handling.
Release preparation
Deployment, operating notes and public-review material where required. Define the support period and the treatment of later review feedback in the proposal.
What would make this pilot ready to accept?
| Situation | Expected behaviour | Evidence to review |
|---|---|---|
| User asks for a matching item | The tool returns relevant items with current identifiers and a source reference. | Compare the result with the source API. |
| No item matches | Report no match and ask for a useful refinement. | Test an empty result without invented products. |
| User lacks access | Reject the operation without exposing another account’s data. | Run with a restricted test account. |
| Quote request is repeated | Follow an agreed duplicate rule rather than silently creating another record. | Inspect the source record and operation history. |
| Upstream API times out | Distinguish an unknown outcome from a confirmed failure before retrying a write. | Simulate a timeout and review recovery. |
The quote stays a draft in this example. Sending it, charging a customer or reserving stock would be separate operations with their own permissions and acceptance tests. We can assess whether a custom interface improves the workflow after the core tools work.
Useful actions need predictable boundaries.
I design the server to validate inputs, enforce user access and expose only the operations the workflow needs. Credentials stay in the configured backend environment. Sensitive changes have an agreed confirmation path; retries must not silently create duplicate records.
For customer-specific data, authentication and account isolation are part of the design. We also decide what information is returned to ChatGPT, what diagnostics retain and how access is revoked. Public listing requirements and your privacy documentation are reviewed before submission.
04 / Cost and timing
Get a proposal based on your workflow.
ChatGPT plugin development cost depends on the number of tools, API readiness, authentication, read versus write access, UI requirements and the work needed for testing and release. A focused read-only integration has a different scope from a product with account linking, write operations and several interactive views.
Send a short description and API documentation if you have it. I will clarify the unknowns and propose a first version with deliverables, pricing or a billing method, milestones and maintenance assumptions. If paid discovery is needed, its cost and output are agreed first.
Timing is estimated after the API and scope review. Public review is a separate dependency: I can prepare a submission and address technical feedback, but OpenAI controls approval, availability and review timing.
Describe the first task you want to support ↗Work directly with the developer building it.
I’m Lukáš Jursa, an independent developer behind Softflow. I develop ChatGPT plugins and API integrations and can work on the backend and workflow around them. My wider software work includes API-driven desktop tools, queued automation, publishing pipelines and browser extensions.
That work involves the same practical concerns: data validation, access, retries, state and a clear handover. See examples of the systems I have built. You discuss technical decisions, scope and progress directly with me.
Prepare a useful first conversation
What does your ChatGPT integration need?
Use these four questions to prepare an enquiry outline. This helps identify what we need to verify before quoting. Your selections stay in your browser until you choose to open an email.
Bring one user task, the source system and any API documentation. For private data, identify the account owner and sign-in method. For writes, describe what changes, who approves it and how to detect duplicate requests.
Questions before you hire a ChatGPT plugin developer
Can the same MCP integration work with Claude or other assistants?
The server-side integration may be reusable with compatible MCP clients, but authentication, transports, tools and interfaces must be checked for each target. Additional client testing and any directory submission are scoped separately.
Will a public listing bring customers or guarantee installs?
A listing can provide another way to discover and use your product. It does not guarantee traffic, recommendations, installs or sales. We agree how to evaluate workflow completion and actual usage after release.
Can you build a ChatGPT plugin for my existing SaaS product?
Yes. I start by reviewing the user task, API capabilities and access rules. We can scope a first workflow around your existing product, then agree which tools, authentication and interface it needs.
Do you develop custom GPT Actions as well as MCP plugins?
Yes. I can build custom GPT Actions using an OpenAPI schema and REST API integration, or a plugin with an MCP server and optional UI. We choose the route that fits the user experience and intended distribution.
How much does ChatGPT plugin development cost?
The cost depends on API readiness, tool count, authentication, write operations, interface requirements and release scope. After reviewing the workflow, I provide a proposal with deliverables, pricing or billing terms and milestones. Paid discovery, if needed, is agreed separately first.
Can you connect ChatGPT to a private API with OAuth?
Yes, subject to the capabilities of your service. We define account linking, permissions, token handling and what each user may access. Sensitive data and write operations need explicit rules and server-side checks.
Can you help with plugin submission and publication?
I can prepare the agreed package, test cases, deployment instructions and technical submission material, and address review feedback within the agreed scope. OpenAI makes the approval decision and controls review timing and platform availability.
Do I need an API before starting?
An existing documented API makes scoping easier. If it is missing, I can assess a backend or adapter as a separate part of the project. Send a description of the system and the first task you want users to perform.
Will I receive the source code and documentation?
Yes. The proposal defines the project code, configuration, deployment notes and operating instructions included in the handover. We also agree who owns the service accounts, pays hosting costs and handles maintenance.
Is this a WordPress plugin or the old ChatGPT plugin beta?
This service focuses on current ChatGPT plugins, MCP integrations and custom GPT Actions. If you have a legacy integration, I can assess which parts can be reused and propose an appropriate migration scope.
Your first workflow
What should a user be able to do in ChatGPT?
Tell me about your product, who will use the integration and the first task they should complete. Include a link to your API documentation if available. A brief description is enough to start.
Email me about your plugin ↗hello@softflow.cz
I usually reply within one business day. Please leave passwords and API keys out of the first email.