Lsp

Atopile LSP via MCP

The atopile LSP (ato lsp start) can be bridged to MCP (e.g. via mcpls). This gives you semantic access to .ato files beyond what grep/read can provide.

The tool names below assume the MCP server is registered as atopile-lsp. If yours is registered under a different name, substitute the prefix accordingly.

When to Use

• Understanding a symbol — hover gives type, members, docs, and usage examples
• Checking for errors — diagnostics surfaces parse errors and warnings after edits
• Navigating code — definition jumps to where a symbol is declared; references finds all usages
• Formatting — format_document applies language-specific formatting rules

Prefer these tools over grep when you need type information, interface members, or documentation.

Working Tools

All position params are 1-indexed (as shown in editors).

| Tool | What it does | Key params | |------|-------------|------------| | mcp__atopile-lsp__get_hover | Type info, docs, members, usage examples | file_path, line, character | | mcp__atopile-lsp__get_diagnostics | Parse errors/warnings for a file | file_path | | mcp__atopile-lsp__get_cached_diagnostics | Same as above but from cache (faster) | file_path | | mcp__atopile-lsp__get_definition | Jump to where a symbol is defined | file_path, line, character | | mcp__atopile-lsp__get_references | Find all usages of a symbol | file_path, line, character, include_declaration | | mcp__atopile-lsp__format_document | Format a file with language rules | file_path |

Tools That May Return Empty

Depending on LSP version, some methods are not yet fully implemented and return no data:

| Tool | Notes | |------|-------| | mcp__atopile-lsp__get_completions | May run but return no items | | mcp__atopile-lsp__get_code_actions | May run but return no actions | | mcp__atopile-lsp__get_document_symbols | textDocument/documentSymbol may be unimplemented | | mcp__atopile-lsp__workspace_symbol_search | workspace/symbol may be unimplemented | | mcp__atopile-lsp__prepare_call_hierarchy | textDocument/prepareCallHierarchy may be unimplemented |

If a tool returns nothing, fall back to grep + get_hover on the located position.

Usage Patterns

Inspect a symbol — use get_hover at the symbol's file position. Returns the type, full member list, and usage examples.

get_hover(file_path=".../some-driver.ato", line=36, character=8)
→ interface ElectricPower: voltage, max_current, hv, lv, gnd, vcc ...

Check a file compiles — use get_diagnostics after editing. Empty diagnostics = file parses clean.

Find a definition — use get_definition at a symbol reference. Returns the source file and line range.

Find all usages — use get_references at a symbol. Returns every location across the workspace.

Explore an unfamiliar interface — grep to find where it's used, then get_hover on that position.

Common Mistakes

• Wrong line/character — 1-indexed, not 0-indexed
• Skipping diagnostics after edits — always verify .ato files parse cleanly

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: mawildoer
• Source: mawildoer/atopile-agent-skill
• License: MIT

Install and usage instructions live in the source repository linked above.