seshat-mcp — Claude Code MCP server: what it does, how to install
Delivers typed symbol graphs, call traces, and change blast radius to AI coding assistants.
claude mcp add seshat-mcp -e SESHAT_API_KEY=<SESHAT_API_KEY> -- npx -y @papyruslabsai/seshat-mcpWhat seshat-mcp does
The server converts your codebase into a typed symbol graph containing functions, classes, routes, and database tables. Instead of text matching or vector embeddings, it relies on a compiled intermediate representation. Tools like get_blast_radius and get_dependencies map exact downstream impacts before modifying any target symbol.
It inspects Git history via get_lineage and get_hotspots to flag fragile areas and unstable commits. For JavaScript, TypeScript, and Python, the query_call_sites tool detects unhandled call failures and unawaited promises. Code investigation starts once you point the agent at a repository with sync_project.
Code analysis runs strictly inside Papyrus Labs infrastructure, meaning the server cannot query without a valid SESHAT_API_KEY. The first repo extraction is free, after which queries cost $0.03 each past the initial tier.
What it helps with
- map transitive blast radius before refactoring a critical symbol
- surface unawaited promises and uncaught errors across call sites
- gather a minimal ranked set of context files for upcoming edits
- track historical commit hotspots and co-changing file clusters
Example prompts for the agent
- Check the blast radius for
handleAuthCallbackbefore altering its signature - Run
query_call_sitesto find floating promises in the API routes - Retrieve the lineage and commit churn data for the checkout module
How to install seshat-mcp
Platform CLI
claude mcp add seshat-mcp -e SESHAT_API_KEY=<SESHAT_API_KEY> -- npx -y @papyruslabsai/seshat-mcpReplace <…> with your own values
Platform CLI
codex mcp add seshat-mcp --env SESHAT_API_KEY=<SESHAT_API_KEY> -- npx -y @papyruslabsai/seshat-mcpReplace <…> with your own values
Config file
{
"mcpServers": {
"seshat-mcp": {
"command": "npx",
"args": [
"-y",
"@papyruslabsai/seshat-mcp"
],
"env": {
"SESHAT_API_KEY": "<SESHAT_API_KEY>"
}
}
}
}Replace <…> with your own values
Config file
{
"servers": {
"seshat-mcp": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@papyruslabsai/seshat-mcp"
],
"env": {
"SESHAT_API_KEY": "<SESHAT_API_KEY>"
}
}
}
}Replace <…> with your own values
Platform CLI
gemini mcp add -e SESHAT_API_KEY=<SESHAT_API_KEY> seshat-mcp npx -y @papyruslabsai/seshat-mcpReplace <…> with your own values
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about seshat-mcp
How to install seshat-mcp in Claude Code?
Run claude mcp add seshat-mcp -e SESHAT_API_KEY=<SESHAT_API_KEY> -- npx -y @papyruslabsai/seshat-mcp in your terminal. Replace the placeholder with the key from your account.
What does seshat-mcp do?
It exposes a compiled dependency graph of your repo to AI tools over MCP. Agents use it to check exact callers, side effects, and structural risks instead of guessing.
Where does the code processing take place?
Extraction happens on Papyrus Labs servers. Public repositories are pulled directly from GitHub, while private repositories need connected GitHub credentials.
