Linchpin / Glossary

Glossary

Definitions for the vocabulary used across the Linchpin docs, comparisons, and use-case pages. Linked from every page on first technical-term use.

  • Managed agent
    An AI agent that runs as a long-lived, externally-managed session rather than a one-shot LLM call. The runtime tracks state, sandboxes tools, persists events, and exposes a control surface over an API. More.
  • Agent runtime
    The platform that runs agents — session lifecycle, tool execution, model calls, event log, streaming. Distinct from an agent library (code you import into your service) and a hosted agent service (someone else's runtime). Linchpin is a runtime. See vs LangGraph.
  • Per-session sandbox
    A dedicated Docker container created for each agent session. Tool calls (bash, file I/O, MCP servers) run inside this container, on a network the operator controls. Isolates the agent from the host machine and from other sessions.
  • Event log
    An append-only record of every event in a session — user messages, agent messages, tool calls, tool results, status transitions. Cursor-paginated, streamable over SSE, replayable from any cursor. Backed by Postgres.
  • MCP Model Context Protocol
    An open standard for connecting LLMs to external tools and data via stdio servers. Linchpin runs MCP servers inside the per-session sandbox so the agent can invoke their tools alongside the built-in eight.
  • OpenRouter
    A model-routing service that exposes ~200 LLMs (Claude, GPT, Gemini, Llama, Mistral, Qwen, and more) through one OpenAI-compatible API. Linchpin uses OpenRouter as its single cloud-model provider — one adapter, every model.
  • Ollama
    A local-first runtime for running LLMs on your own machine. Linchpin's ollama provider points at a local Ollama server so agents can run entirely offline against local model weights. See local-LLM agents.
  • SSE Server-Sent Events
    A one-way streaming protocol over HTTP. Linchpin uses SSE to push event-log updates and token deltas to clients. Simpler than WebSockets, HTTP-native, replayable from a cursor.
  • Fernet
    A symmetric encryption recipe (AES-128-CBC + HMAC-SHA256) from the Python cryptography library. Linchpin's credential vault encrypts secrets with Fernet using VAULT_ENCRYPTION_KEY, supplied at startup and never persisted.
  • Self-hostable
    Software that can be installed and operated on infrastructure owned by the user — not a hosted service. Linchpin is self-hostable: clone, configure, run on your own VM with docker compose. See self-hosted agents.