agent-lsp

Overview

agent-lsp is a stateful runtime that bridges language servers and AI agents, providing 65+ tools for type-aware code navigation, blast-radius analysis, and pre-verified edits. It solves the problem of AI agents making incorrect code changes by giving them full visibility into code structure, dependencies, and potential impacts. The solution indexes workspaces once, keeps the index warm, and adds a skill layer that encodes correct multi-step operations. Unlike other MCP-LSP implementations, it has been CI-verified against 30 real language servers and offers unique features like speculative execution and phase enforcement.

Try asking AI

After installing, here are 5 things you can ask your AI assistant:

• blast_radius

  Find all call sites of a symbol with test/non-test partitioning

  Try:Show me where this function is usedTry:Find all callers of this method
• go_to_implementation

  Find all concrete implementations of an interface

  Try:Show me all implementations of this interfaceTry:Find types that implement this protocol
• preview_edit

  Preview the diagnostic impact of an edit without writing to disk

  Try:What would break if I change this function?Try:Preview errors before saving this edit
• simulate_chain

  Evaluate a sequence of dependent edits and find where the first error occurs

  Try:Simulate renaming a function and updating all its callersTry:Test a refactoring chain step by step
• find_references

  Find all references to a symbol in the codebase

  Try:Where is this variable used?Try:Find all occurrences of this function
• get_diagnostics

  Get current diagnostic issues (errors, warnings) in a file or workspace

  Try:Show me all errors in this fileTry:Check for any issues in the project
• replace_symbol_body

  Replace the implementation of a symbol while preserving its signature

  Try:Replace the body of this functionTry:Update the implementation of this method
• safe_apply_edit

  Preview edits and apply to disk only if no new errors are introduced

  Try:Make this change but only if it doesn't break anythingTry:Apply this edit safely after previewing
• find_callers

  Find functions that call a specific symbol

  Try:What calls this function?Try:Find all callers of this method
• get_definition

  Go to the definition location of a symbol

  Try:Where is this function defined?Try:Show me the definition of this variable
• get_hover

  Get hover information (type, documentation) for a symbol

  Try:Show me the type of this variableTry:What does this function do?
• safe_delete_symbol

  Delete a symbol safely after finding all its references

  Try:Delete this function but first check where it's usedTry:Safely remove this unused variable

Comparable tools

Installation

go install github.com/blackwell-systems/agent-lsp@latest

{
  "mcpServers": {
    "agent-lsp": {
      "command": "agent-lsp",
      "args": ["stdio"]
    }
  }
}

FAQ

What languages are supported?

agent-lsp supports 30+ CI-verified languages including Go, TypeScript, Python, Rust, Java, C/C++, C#, Ruby, PHP, Kotlin, Swift, Scala, Zig, Lua, Elixir, and more. Each language server is actually tested in CI.

How does agent-lsp differ from other MCP-LSP implementations?

Unlike other implementations, agent-lsp is a stateful runtime that keeps indexes warm, offers CI-verified language server support, provides speculative execution capabilities, enforces workflow phases, and includes features like concurrency analysis and token savings.

Compare agent-lsp with