sem
Semantic version control => entity-level diffs, blame, and impact analysis on top of git. 28 languages via tree-sitter. Built for coding agents.
Sem is a semantic version control tool that layers entity-level analysis on top of Git, parsing code with tree-sitter to identify functions, classes, and methods across 32 programming languages. Instead of tracking line-by-line changes, it reports which specific entities (functions, classes, methods) were modified, renamed, or moved, with cross-file dependency graphs and impact analysis. It serves both as a CLI for developers and as an MCP server for AI coding agents (Claude Code, Claude Desktop, Cursor) so agents can query 'what breaks if I change this function' or 'give me context for refactoring this entity' without reading entire files. The tool supports entity-level diffs, blame, commit history tracking, hotspot analysis, and token-budgeted context extraction tailored for LLM workflows.
Key Features
Use Cases
- 01AI coding agents querying which tests or modules break before modifying a function
- 02Code reviewers seeing exactly which functions changed in a PR, ignoring whitespace and formatting noise
- 03Developers tracking how a specific function evolved through git history without wading through line diffs
- 04LLM-assisted refactoring using token-budgeted context that includes only relevant dependencies
- 05CI/CD pipelines getting JSON entity-level diffs for automated analysis or reporting
- 06Teams using shared cloud graph in large monorepos to avoid rebuilding dependency graphs per developer
Related MCP Servers
View moremarkitdown
Python tool for converting files and office documents to Markdown.
firecrawl
The context API to search, scrape, and interact with the web at scale. 🔥
prompts.chat
f.k.a. Awesome ChatGPT Prompts. Share, discover, and collect prompts from the community. Free and open source — self-host for your organization with complete privacy.
langflow
Langflow is a powerful tool for building and deploying AI-powered agents and workflows.
sem — FAQ
What is sem?+
Sem is a semantic version control tool built on Git that parses code with tree-sitter and tracks changes at the entity level (functions, classes, methods) instead of lines. It also exposes an MCP server so AI coding agents can query dependency graphs, impact analysis, and context without reading full files.
How do I install sem?+
Install via the install script (curl -fsSL https://raw.githubusercontent.com/Ataraxy-Labs/sem/main/install.sh | sh), Homebrew (brew install sem-cli), npm (npm install --save-dev @ataraxy-labs/sem), or download binaries from GitHub Releases. For MCP server usage in Claude Code, run 'claude mcp add sem -- sem mcp' or 'npx @ataraxy-labs/sem-skill' to add both the server and skill.
Which AI clients does the sem MCP server work with?+
The sem MCP server works with Claude Code, Claude Desktop, Cursor, and any MCP-compatible client that supports stdin/stdout MCP servers. Add it to the mcpServers config with command 'sem' and args ['mcp'].
Does sem require API keys or cloud login?+
No API keys are required and login is optional. Sem runs entirely locally by default, with no cloud dependency. Cloud login (sem login) is opt-in for large repos where a shared warm graph speeds up queries, but local computation is always available and produces identical results.
Is sem free to use?+
Yes, sem is open-source under MIT OR Apache-2.0 license. Local usage is always free; cloud-backed queries for large repos are available after login but entirely optional.
What programming languages does sem support?+
Sem supports 32 languages including TypeScript, JavaScript, Python, Go, Rust, Java, C/C++, C#, Ruby, PHP, Swift, Elixir, Bash, Kotlin, Fortran, Vue, Svelte, Dart, OCaml, Scala, Haskell, Elm, Clojure, Zig, and SQL, plus structured formats like JSON, YAML, TOML, CSV, and Markdown. Files with unsupported extensions fall back to chunk-based diffing.
How do I install sem?+
Open the source repository on GitHub and follow its README. sem is a mcp server — MCP Agents Market links you directly to the official repo.
Is sem free?+
sem is an open-source project hosted on GitHub. Check the repository for its license and any usage requirements.