Lsp Architecture

Requires the agent-lsp MCP server.

lsp-architecture

Generate a structural architecture overview of any codebase: language distribution, package hierarchy, entry points, dependency flow, and hotspot files. One invocation for the big picture.

Read-only; does not modify any files.

Invocation: User provides the workspace root path (e.g. "/home/user/myproject"). If omitted, use the current working directory.

Depth Controls (hard limits)

These limits are strict constraints. Never exceed them:

• Package enumeration: cap at 30 packages
• Hotspot analysis: cap at 10 files
• Workspace symbol queries: cap at 5 queries
• Do NOT recurse into vendor/, node_modules/, .git/, or other dependency directories

Step 0 — Initialize

If LSP is not yet running, start it with the workspace root:

mcp__lsp__start_lsp({
  "workspace_root": "<workspace-root>"
})

Then detect which language servers are available:

mcp__lsp__detect_lsp_servers({
  "workspace_root": "<workspace-root>"
})
→ returns: list of detected servers with language names and file patterns

Record the available languages and their file globs. This determines which queries to run in later steps.

Step 1 — Language Detection

Scan the workspace to determine language distribution. Use file extension counts from the detected servers and supplement with a filesystem scan (via Glob tool) to count files per language.

For each detected language, report:

• Language name
• File count
• Estimated lines of code (sample 3-5 representative files and extrapolate)

Skip files in vendor/, node_modules/, .git/, dist/, build/, and other common dependency or output directories.

Step 2 — Package Structure

Use find_symbol with broad queries to discover the package and module hierarchy. Tailor queries by language:

Go:

mcp__lsp__find_symbol({
  "query": "",
  "symbol_kind_filter": "Package"
})

Also query for top-level types and functions to fill in package-level detail:

mcp__lsp__find_symbol({
  "query": "",
  "symbol_kind_filter": "Function"
})

Python:

mcp__lsp__find_symbol({
  "query": "",
  "symbol_kind_filter": "Class"
})

TypeScript/JavaScript:

mcp__lsp__find_symbol({
  "query": "",
  "symbol_kind_filter": "Function"
})

From the returned symbols, extract the directory paths and build a tree of the package hierarchy. Group symbols by their containing directory. For each package/directory, note:

• Path relative to workspace root
• Brief description (inferred from symbol names and directory name)
• Approximate symbol count

Cap at 30 packages. If more than 30 directories contain symbols, keep only the top 30 by symbol count and note that others were omitted.

Cap workspace symbol queries at 5 total across all of Step 2.

Step 3 — Entry Points

Use find_symbol to search for common entry point patterns:

mcp__lsp__find_symbol({
  "query": "main"
})

Also search for other common entry point names (use a single additional query if needed): "Run", "Serve", "Handler", "App", "Main".

Identify and categorize:

• CLI entrypoints: main functions, Run or Execute commands
• HTTP handlers: Handler, Serve, ListenAndServe patterns
• Test suites: top-level test files (note count only, do not list individually)

List each entry point with file:line.

Step 4 — Hotspot Analysis

Identify the files with the highest symbol density (most exports), then measure their blast radius.

4a — Find candidate files

From the symbols discovered in Step 2, count exported symbols per file. Select the top 10 files by exported symbol count.

4b — Measure blast radius

For each candidate file, call blast_radius:

mcp__lsp__blast_radius({
  "changed_files": ["<absolute-path-to-file>"],
  "include_transitive": false
})
→ returns: affected_symbols, test_callers, non_test_callers

This tool uses a persistent cache, so repeated calls on the same file are instant.

4c — Rank hotspots

Rank files by total non_test_callers count (descending). Files with the most non-test callers are the architectural hotspots: changing them has the widest blast radius.

Step 5 — Output

Produce the architecture report in this format:

## Architecture Overview: <project-name>

### Languages
- Go: 150 files (~15K lines)
- TypeScript: 30 files (~3K lines)

### Package Map
cmd/agent-lsp/     (entrypoint, CLI routing)
internal/lsp/      (LSP client, process management)
internal/tools/    (MCP tool handlers)
internal/session/  (speculative execution sessions)
...

### Entry Points
- cmd/agent-lsp/main.go:55 (main)
- cmd/agent-lsp/server.go:276 (Run)

### Hotspots (most referenced files)
1. internal/lsp/client.go: 150+ callers across 30 files
2. internal/tools/helpers.go: 80 callers across 20 files
...

### Dependency Flow
cmd/ -> internal/tools/ -> internal/lsp/ -> (gopls subprocess)
         |-> internal/session/ -> internal/lsp/

Report sections

Languages: One line per language with file count and estimated LOC.

Package Map: Directory tree with a parenthetical description of each package's role. Cap at 30 entries.

Entry Points: Each with file:line and a parenthetical label (e.g. (main), (HTTP handler), (CLI command)).

Hotspots: Ranked list of the most-referenced files. For each, show the total non-test caller count and the number of distinct files containing callers.

Dependency Flow: A simple ASCII arrow diagram showing how the top-level packages depend on each other. Infer this from the hotspot caller data and package structure. Keep it concise: show the primary flow paths, not every edge.

Example

Goal: architecture overview of /home/user/agent-lsp

Step 0 — Initialize
  start_lsp: workspace_root="/home/user/agent-lsp"
  detect_lsp_servers:
  → Go (gopls): *.go
  → detected 1 language server

Step 1 — Language Detection
  Glob: **/*.go (excluding vendor/) → 85 files
  Sample 5 files, average 180 lines → estimate ~15K total lines
  → Go: 85 files (~15K lines)

Step 2 — Package Structure
  find_symbol: query="", symbol_kind_filter="Package"
  → 12 packages found

  find_symbol: query="", symbol_kind_filter="Function"
  → 240 functions across 12 packages

  Package map:
    cmd/agent-lsp/       (entrypoint, CLI routing, 15 symbols)
    internal/lsp/        (LSP client lifecycle, 45 symbols)
    internal/tools/      (MCP tool handlers, 60 symbols)
    internal/session/    (speculative execution, 25 symbols)
    internal/protocol/   (LSP protocol types, 30 symbols)
    skills/              (embedded skill definitions, 5 symbols)

Step 3 — Entry Points
  find_symbol: query="main"
  → cmd/agent-lsp/main.go:55 main()

  find_symbol: query="Run"
  → cmd/agent-lsp/server.go:276 Run()
  → cmd/agent-lsp/daemon.go:40 RunDaemon()

  Entry points:
  - cmd/agent-lsp/main.go:55 (main)
  - cmd/agent-lsp/server.go:276 (Run, server lifecycle)
  - cmd/agent-lsp/daemon.go:40 (RunDaemon, background mode)

Step 4 — Hotspot Analysis
  Top files by symbol count:
    1. internal/lsp/client.go (22 exported symbols)
    2. internal/tools/helpers.go (18 exported symbols)
    3. internal/protocol/types.go (15 exported symbols)

  blast_radius on each:
    internal/lsp/client.go → 150 non-test callers across 30 files
    internal/tools/helpers.go → 80 non-test callers across 20 files
    internal/protocol/types.go → 60 non-test callers across 15 files

Step 5 — Output

## Architecture Overview: agent-lsp

### Languages
- Go: 85 files (~15K lines)

### Package Map
cmd/agent-lsp/       (entrypoint, CLI routing)
internal/lsp/        (LSP client, process management)
internal/tools/      (MCP tool handlers)
internal/session/    (speculative execution sessions)
internal/protocol/   (LSP protocol types)
skills/              (embedded skill definitions)

### Entry Points
- cmd/agent-lsp/main.go:55 (main)
- cmd/agent-lsp/server.go:276 (Run)
- cmd/agent-lsp/daemon.go:40 (RunDaemon)

### Hotspots (most referenced files)
1. internal/lsp/client.go: 150 callers across 30 files
2. internal/tools/helpers.go: 80 callers across 20 files
3. internal/protocol/types.go: 60 callers across 15 files

### Dependency Flow
cmd/agent-lsp/ -> internal/tools/ -> internal/lsp/ -> (gopls subprocess)
                    |-> internal/session/ -> internal/lsp/
                    |-> internal/protocol/