Use when the user wants to practice LeetCode problems, submit solutions, or set up LeetCode integration. Covers MCP server installation, learning-guided practice flow, solution submission, and authentication.
Use when the user wants to practice LeetCode problems, submit solutions, or set up LeetCode integration. Covers MCP server installation, learning-guided practice flow, solution submission, and authentication.
MCP server for LeetCode practice with learning-guided hints, solution submission, and AI-driven authentication.
Prerequisite: Ensure MCP Server Is Connected
Before anything else, check whether the get_started tool is available. If it is, the server is connected — skip to the next section.
If get_started is NOT available, the MCP server needs to be installed. Ask the user for confirmation before proceeding — explain that this will download and run an npm package.
The npm package is (source: ). It runs over stdio transport. Requires Node.js >= 20.
claude mcp add --transport stdio leetcode -- npx -y @sperekrestova/interactive-leetcode-mcp@3.2.4
Pin a specific version (shown above) rather than using @latest to avoid executing untested code. Users can check for newer versions at the npm page or GitHub releases and update the pinned version after reviewing the changelog.
After adding the server, tell the user to restart their session so the MCP tools become available. Do not proceed with the session flow until get_started is accessible.
First Action: Always Call get_started
At the START of every LeetCode session, call the get_started tool. It returns the full usage guide: prompt invocation rules, session flow, learning mode rules, auth flow, and language map.
Do not skip this — it is a single fast call, not redundant with tool descriptions. The server has MCP prompts that must be explicitly invoked — they are NOT auto-active. The get_started response tells you exactly when and how.
Session Flow (Critical)
1. Call get_started <-- FIRST, every session
2. Invoke leetcode_learning_mode <-- BEFORE any problem discussion
3. User picks a problem
4. Invoke leetcode_problem_workflow(problemSlug, difficulty)
5. Invoke leetcode_workspace_setup(language, problemSlug, codeTemplate)
6. Guide user with progressive hints (4 levels)
7. submit_solution when ready
Steps 2, 4, and 5 are MCP prompt invocations. Invoke them via the Skill tool or equivalent prompt mechanism. All three must happen BEFORE the user starts coding.
Step 2 is non-negotiable. If you skip leetcode_learning_mode, you will bypass the progressive hint system and may show solutions prematurely. Invoke it before searching for or discussing any problem.
Prompt Invocation Rules
Prompt
When
Params
leetcode_learning_mode
START of session, before any problem
none
leetcode_problem_workflow
After user selects a problem
problemSlug, difficulty
leetcode_workspace_setup
Before user starts coding
language, problemSlug, codeTemplate
leetcode_authentication_guide
On auth need, 401 errors, expired creds
none
Learning Mode Rules
Never show a full solution without working through hint levels 1 → 2 → 3
Level 1: Guiding questions ("What pattern do you see?")
Level 2: General approaches ("Consider using a hash map...")
Level 3: Specific hints ("Iterate once, tracking seen values...")
Level 4: Pseudocode or partial implementation
Only show complete solutions when explicitly requested AFTER earlier hints
get_problem_solution returns full community solutions — Level 4 or explicit request only
Tool Quick Reference
Tool
Purpose
Auth?
get_daily_challenge
Today's challenge
No
get_problem
Problem by slug
No
search_problems
Find by tags/difficulty/keywords
No
list_problem_solutions
Solution metadata (topicIds)
No
get_problem_solution
Full solution — Level 4 only
No
submit_solution
Submit code
No*
get_user_profile
Any user's stats
No
get_recent_submissions
Recent submissions
No
get_recent_ac_submissions
Accepted submissions
No
get_user_contest_ranking
Contest ranking
No
start_leetcode_auth
Start auth flow
No
save_leetcode_credentials
Validate + save creds
No
check_auth_status
Check credential state
No
get_user_status
Current user info
Yes
get_problem_submission_report
Submission detail
Yes
get_problem_progress
Progress with filters
Yes
get_all_submissions
All submissions
Yes
*submit_solution requires saved credentials to succeed.
Auth Flow
Before auth-sensitive actions → call check_auth_status
If not authenticated or expired → ask the user if they want to authenticate. Explain that this will store LeetCode session cookies locally at ~/.leetcode-mcp/credentials.json (owner-read/write only). Do not proceed without consent.
After consent → invoke leetcode_authentication_guide prompt
Call start_leetcode_auth → the prompt will guide the user through providing credentials → call save_leetcode_credentials with the values the user provides
On success → retry original action
On 401 from any tool → repeat from step 1
Always delegate auth guidance to the leetcode_authentication_guide prompt. Do not improvise your own auth instructions — the prompt handles browser-specific guidance, error recovery, and troubleshooting.
Credential storage: The MCP server stores credentials locally at ~/.leetcode-mcp/credentials.json with file permissions 0o600 (owner-read/write only). Only csrftoken, LEETCODE_SESSION, and a createdAt timestamp are stored. Credentials are never transmitted to any third party — they are used exclusively for direct LeetCode API calls. Typical credential lifetime is 7-14 days.
Submission Language Map
User says
Pass to submit_solution
Python / Python 3
python3
Python 2
python
Java
java
C++
cpp
JavaScript
javascript
TypeScript
typescript
Default: "Python" without version → python3.
Resources (Read-Only Lookups)
Resource URI
What it provides
categories://problems/all
All problem categories
tags://problems/all
All 60+ topic tags
langs://problems/all
All supported submission languages
problem://{titleSlug}
Problem detail
solution://{topicId}
Solution detail (same learning-mode rules apply)
Common Mistakes
Jumping to problem search before invoking leetcode_learning_mode
Showing full solutions without progressing through hint levels 1 → 2 → 3
Not invoking leetcode_workspace_setup — code should live in a file, not only in chat
Guiding auth manually instead of invoking leetcode_authentication_guide
Passing "Python" to submit_solution instead of "python3"
Not calling check_auth_status before auth-sensitive operations
Skipping get_started and assuming tool descriptions are sufficient
