PrepGraph is an interview preparation tool. It holds a bank of 306 practice questions across product management, data science, data engineering and AI product tracks, plus a personal concept graph each user builds while studying. This connector lets an AI assistant read your own study data, browse the question bank, and save new concepts as they come up in conversation.
| MCP server URL | https://getprepgraph.com/api/mcp |
|---|---|
| Transport | Streamable HTTP over HTTPS. POST only; GET returns 405. |
| Authentication | OAuth 2.1, authorization code with PKCE (S256 required). A first party API key is also accepted. |
| Registration | Dynamic client registration (RFC 7591) at POST /api/oauth/register. No pre-approval needed. |
An unauthenticated request returns 401 with a WWW-Authenticate header naming
the resource metadata document, so a compliant client needs nothing but the endpoint URL to begin.
| URL | Returns |
|---|---|
/.well-known/oauth-protected-resource/api/mcp | Protected resource metadata (RFC 9728) |
/.well-known/oauth-authorization-server | Authorization server metadata (RFC 8414) |
Six tools are available to connectors. Five read, one writes. Every tool is scoped to the account that authorised the connection, and no argument can widen that scope to another user.
| Tool | What it does | Access |
|---|---|---|
get_profile | Your name, email, plan, AI sessions used and current streak. | Read |
get_concepts | Concepts you have saved, filterable by topic and by mastery level. | Read |
get_practice_activity | Your practice sessions grouped by date. | Read |
get_billing_status | Your plan, AI sessions used and remaining. | Read |
get_arena_concepts | Browse the shared question bank by track, topic or keyword. Returns the question and its hints. | Read |
add_concept | Saves a new concept to your workshop, optionally filed under a topic. | Write |
Every tool carries MCP annotations (readOnlyHint, destructiveHint,
idempotentHint, openWorldHint), so a host can enforce a read only connection
without parsing descriptions. add_concept is the only tool that changes anything, and it is
additive: it creates a new record and never edits or deletes an existing one.
https://getprepgraph.com/api/mcp to your assistant as a connector or MCP server.You can revoke access at any time by contacting [email protected], and a self service disconnect control is in progress.
Ask: "Give me a data science interview question on experimentation to practise."
What happens: the assistant calls get_arena_concepts with
track: "ds" and topic: "Experimentation".
Expected result: a question with its hints, in the shape below.
## A/B test design [ds · Experimentation]
**Question:** Walk me through how you would design an A/B test for a new
recommendation algorithm.
**Hints:**
- Defines hypothesis, unit of randomisation, primary + guardrail metrics
- Calculates sample size and runtime upfront
- Addresses novelty effects (new algorithm looks good initially)
- Plans for partial rollout before full ship
Other prompts that work well:
| Requirement | Detail |
|---|---|
| Account | A free PrepGraph account is required. Sign up at getprepgraph.com. |
| Free plan | All six tools work. The question bank returns introductory and intermediate questions. |
| Pro plan | 9 euros per month. Adds advanced questions to get_arena_concepts. |
| AI quota | Connector calls do not consume the account's AI session allowance. |
| Result size | get_arena_concepts returns at most 50 items per call. |
| Rate limits | None enforced today. We may introduce per client limits and will document them here first. |
| Regions | PrepGraph is available worldwide. Our users are concentrated in Ireland and Bangladesh. |
A connector reads only the data belonging to the account that authorised it. What an assistant then does with that data is governed by that assistant's own privacy policy, not ours. Full detail on what we collect, which processors receive it and how long we keep it is in the Privacy Policy, section 5 of which covers connectors specifically.