Extract library_tools + resources; fix 3 dead resources

ltspice://symbols, ltspice://examples, ltspice://status raised TypeError on
read -- they called list_symbols/list_examples/check_installation, which are
@mcp.tool() FunctionTool objects (not callable). Split those three into plain
*_impl functions + thin tool wrappers, and point the resources at the impls.
The other library tools move verbatim.

Adds test_resources.py to read every resource (regression guard). Library tool
outputs verified byte-identical old-vs-new. server.py: 2168 -> 1876 lines.

src/mcltspice/library_tools.py

@@ -0,0 +1,254 @@
+"""Library & model browsing tools: symbols, examples, symbol info, model and
+subcircuit search, and installation check.
+
+The three functions that resources also need (symbols, examples, installation)
+are split into a plain *_impl function plus a thin @mcp.tool() wrapper, so both
+the tool and the resource call the same callable. (A @mcp.tool()-decorated name
+is a FunctionTool and is NOT callable directly.)
+"""
+
+from pathlib import Path
+
+from ._app import mcp
+from .config import (
+    LTSPICE_DIR,
+    LTSPICE_EXAMPLES,
+    LTSPICE_EXE,
+    LTSPICE_LIB,
+    WINE_PREFIX,
+    validate_installation,
+)
+from .models import search_models as _search_models
+from .models import search_subcircuits as _search_subcircuits
+
+
+def list_symbols_impl(
+    category: str | None = None,
+    search: str | None = None,
+    limit: int = 50,
+) -> dict:
+    """Core logic for list_symbols (callable; the tool wrapper delegates here)."""
+    symbols = []
+    sym_dir = LTSPICE_LIB / "sym"
+
+    if not sym_dir.exists():
+        return {"error": "Symbol library not found", "symbols": [], "total_count": 0}
+
+    for asy_file in sym_dir.rglob("*.asy"):
+        rel_path = asy_file.relative_to(sym_dir)
+        cat = str(rel_path.parent) if rel_path.parent != Path(".") else "misc"
+        name = asy_file.stem
+
+        if category and cat.lower() != category.lower():
+            continue
+        if search and search.lower() not in name.lower():
+            continue
+
+        symbols.append({"name": name, "category": cat, "path": str(asy_file)})
+
+    symbols.sort(key=lambda x: x["name"].lower())
+    total = len(symbols)
+    return {"symbols": symbols[:limit], "total_count": total, "returned_count": min(limit, total)}
+
+
+def list_examples_impl(
+    category: str | None = None,
+    search: str | None = None,
+    limit: int = 50,
+) -> dict:
+    """Core logic for list_examples (callable; the tool wrapper delegates here)."""
+    examples = []
+
+    if not LTSPICE_EXAMPLES.exists():
+        return {"error": "Examples not found", "examples": [], "total_count": 0}
+
+    for asc_file in LTSPICE_EXAMPLES.rglob("*.asc"):
+        rel_path = asc_file.relative_to(LTSPICE_EXAMPLES)
+        cat = str(rel_path.parent) if rel_path.parent != Path(".") else "misc"
+        name = asc_file.stem
+
+        if category and cat.lower() != category.lower():
+            continue
+        if search and search.lower() not in name.lower():
+            continue
+
+        examples.append({"name": name, "category": cat, "path": str(asc_file)})
+
+    examples.sort(key=lambda x: x["name"].lower())
+    total = len(examples)
+    return {"examples": examples[:limit], "total_count": total, "returned_count": min(limit, total)}
+
+
+def check_installation_impl() -> dict:
+    """Core logic for check_installation (callable; the tool wrapper delegates here)."""
+    ok, msg = validate_installation()
+    return {
+        "valid": ok,
+        "message": msg,
+        "paths": {
+            "ltspice_dir": str(LTSPICE_DIR),
+            "ltspice_exe": str(LTSPICE_EXE),
+            "wine_prefix": str(WINE_PREFIX),
+            "lib_dir": str(LTSPICE_LIB),
+            "examples_dir": str(LTSPICE_EXAMPLES),
+        },
+        "lib_exists": LTSPICE_LIB.exists(),
+        "examples_exist": LTSPICE_EXAMPLES.exists(),
+    }
+
+
+@mcp.tool()
+def list_symbols(
+    category: str | None = None,
+    search: str | None = None,
+    limit: int = 50,
+) -> dict:
+    """List available component symbols from LTspice library.
+
+    Args:
+        category: Filter by category (e.g., "Opamps", "Comparators")
+        search: Search term for symbol name (case-insensitive)
+        limit: Maximum results to return
+    """
+    return list_symbols_impl(category=category, search=search, limit=limit)
+
+
+@mcp.tool()
+def list_examples(
+    category: str | None = None,
+    search: str | None = None,
+    limit: int = 50,
+) -> dict:
+    """List example circuits from LTspice examples library.
+
+    Args:
+        category: Filter by category folder
+        search: Search term for example name
+        limit: Maximum results to return
+    """
+    return list_examples_impl(category=category, search=search, limit=limit)
+
+
+@mcp.tool()
+def get_symbol_info(symbol_path: str) -> dict:
+    """Get detailed information about a component symbol.
+
+    Reads the .asy file to extract pin names, attributes, and description.
+
+    Args:
+        symbol_path: Path to .asy symbol file
+    """
+    path = Path(symbol_path)
+    if not path.exists():
+        return {"error": f"Symbol not found: {symbol_path}"}
+
+    content = path.read_text(errors="replace")
+    lines = content.split("\n")
+
+    info = {
+        "name": path.stem,
+        "pins": [],
+        "attributes": {},
+        "description": "",
+        "prefix": "",
+        "spice_prefix": "",
+    }
+
+    for line in lines:
+        line = line.strip()
+
+        if line.startswith("PIN"):
+            parts = line.split()
+            if len(parts) >= 5:
+                info["pins"].append(
+                    {
+                        "x": int(parts[1]),
+                        "y": int(parts[2]),
+                        "justification": parts[3],
+                        "rotation": parts[4] if len(parts) > 4 else "0",
+                    }
+                )
+
+        elif line.startswith("PINATTR PinName"):
+            pin_name = line.split(None, 2)[2] if len(line.split()) > 2 else ""
+            if info["pins"]:
+                info["pins"][-1]["name"] = pin_name
+
+        elif line.startswith("SYMATTR"):
+            parts = line.split(None, 2)
+            if len(parts) >= 3:
+                attr_name = parts[1]
+                attr_value = parts[2]
+                info["attributes"][attr_name] = attr_value
+                if attr_name == "Description":
+                    info["description"] = attr_value
+                elif attr_name == "Prefix":
+                    info["prefix"] = attr_value
+                elif attr_name == "SpiceModel":
+                    info["spice_prefix"] = attr_value
+
+    return info
+
+
+@mcp.tool()
+def search_spice_models(
+    search: str | None = None,
+    model_type: str | None = None,
+    limit: int = 50,
+) -> dict:
+    """Search for SPICE .model definitions in the library.
+
+    Finds transistors, diodes, and other discrete devices.
+
+    Args:
+        search: Search term for model name (case-insensitive)
+        model_type: Filter by type: NPN, PNP, NMOS, PMOS, D, NJF, PJF
+        limit: Maximum results
+    """
+    models = _search_models(search=search, model_type=model_type, limit=limit)
+    return {
+        "models": [
+            {
+                "name": m.name,
+                "type": m.type,
+                "source_file": m.source_file,
+                "parameters": m.parameters,
+            }
+            for m in models
+        ],
+        "total_count": len(models),
+    }
+
+
+@mcp.tool()
+def search_spice_subcircuits(
+    search: str | None = None,
+    limit: int = 50,
+) -> dict:
+    """Search for SPICE .subckt definitions (op-amps, ICs, etc.).
+
+    Args:
+        search: Search term for subcircuit name
+        limit: Maximum results
+    """
+    subs = _search_subcircuits(search=search, limit=limit)
+    return {
+        "subcircuits": [
+            {
+                "name": s.name,
+                "pins": s.pins,
+                "pin_names": s.pin_names,
+                "description": s.description,
+                "source_file": s.source_file,
+                "n_components": s.n_components,
+            }
+            for s in subs
+        ],
+        "total_count": len(subs),
+    }
+
+
+@mcp.tool()
+def check_installation() -> dict:
+    """Verify LTspice and Wine are properly installed."""
+    return check_installation_impl()

src/mcltspice/resources.py

@@ -0,0 +1,73 @@
+"""MCP resources exposing library inventories and templates as JSON.
+
+These call the *_impl functions in library_tools (not the @mcp.tool() wrappers,
+which are FunctionTool objects and not callable) so a resource read returns data
+instead of raising TypeError.
+"""
+
+import json
+
+from ._app import mcp
+from .library_tools import check_installation_impl, list_examples_impl, list_symbols_impl
+from .templates import ASC_TEMPLATES, NETLIST_TEMPLATES
+
+
+@mcp.resource("ltspice://symbols")
+def resource_symbols() -> str:
+    """All available LTspice symbols organized by category."""
+    return json.dumps(list_symbols_impl(limit=10000), indent=2)
+
+
+@mcp.resource("ltspice://examples")
+def resource_examples() -> str:
+    """All LTspice example circuits."""
+    return json.dumps(list_examples_impl(limit=10000), indent=2)
+
+
+@mcp.resource("ltspice://status")
+def resource_status() -> str:
+    """Current LTspice installation status."""
+    return json.dumps(check_installation_impl(), indent=2)
+
+
+@mcp.resource("ltspice://templates")
+def resource_templates() -> str:
+    """All available circuit templates (netlist and schematic) with parameters."""
+    templates = {
+        "netlist_templates": [
+            {"name": name, "description": info["description"], "params": info["params"]}
+            for name, info in NETLIST_TEMPLATES.items()
+        ],
+        "schematic_templates": [
+            {"name": name, "description": info["description"], "params": info["params"]}
+            for name, info in ASC_TEMPLATES.items()
+        ],
+    }
+    return json.dumps(templates, indent=2)
+
+
+@mcp.resource("ltspice://template/{name}")
+def resource_template_detail(name: str) -> str:
+    """Detailed information about a specific circuit template."""
+    # Check both registries
+    netlist_info = NETLIST_TEMPLATES.get(name)
+    asc_info = ASC_TEMPLATES.get(name)
+
+    if not netlist_info and not asc_info:
+        return json.dumps({"error": f"Template '{name}' not found"})
+
+    result = {"name": name}
+    if netlist_info:
+        result["netlist"] = {
+            "description": netlist_info["description"],
+            "params": netlist_info["params"],
+            "type": "netlist (.cir)",
+        }
+    if asc_info:
+        result["schematic"] = {
+            "description": asc_info["description"],
+            "params": asc_info["params"],
+            "type": "schematic (.asc)",
+        }
+
+    return json.dumps(result, indent=2)

src/mcltspice/server.py

@@ -11,7 +11,6 @@ This server provides tools for:
 
 import csv
 import io
-import json
 import math
 import tempfile
 from pathlib import Path
@@ -21,23 +20,16 @@ from fastmcp.prompts import Message
 
 # Domain modules register their tools/resources/prompts on the shared mcp
 # instance at import time. Imported for that side effect only.
-from . import spicebook_tools  # noqa: F401,E402
+from . import library_tools, resources, spicebook_tools  # noqa: F401,E402
 from ._app import mcp
 from .batch import (
     run_monte_carlo,
     run_parameter_sweep,
     run_temperature_sweep,
 )
-from .config import (
-    LTSPICE_EXAMPLES,
-    LTSPICE_LIB,
-    validate_installation,
-)
 from .diff import diff_schematics as _diff_schematics
 from .drc import run_drc as _run_drc
 from .log_parser import parse_log
-from .models import search_models as _search_models
-from .models import search_subcircuits as _search_subcircuits
 from .netlist import Netlist
 from .noise_analysis import (
     compute_noise_metrics,
@@ -1563,290 +1555,6 @@ def list_templates() -> dict:
     }
 
 
-# ============================================================================
-# LIBRARY & MODEL TOOLS
-# ============================================================================
-
-
-@mcp.tool()
-def list_symbols(
-    category: str | None = None,
-    search: str | None = None,
-    limit: int = 50,
-) -> dict:
-    """List available component symbols from LTspice library.
-
-    Args:
-        category: Filter by category (e.g., "Opamps", "Comparators")
-        search: Search term for symbol name (case-insensitive)
-        limit: Maximum results to return
-    """
-    symbols = []
-    sym_dir = LTSPICE_LIB / "sym"
-
-    if not sym_dir.exists():
-        return {"error": "Symbol library not found", "symbols": [], "total_count": 0}
-
-    for asy_file in sym_dir.rglob("*.asy"):
-        rel_path = asy_file.relative_to(sym_dir)
-        cat = str(rel_path.parent) if rel_path.parent != Path(".") else "misc"
-        name = asy_file.stem
-
-        if category and cat.lower() != category.lower():
-            continue
-        if search and search.lower() not in name.lower():
-            continue
-
-        symbols.append({"name": name, "category": cat, "path": str(asy_file)})
-
-    symbols.sort(key=lambda x: x["name"].lower())
-    total = len(symbols)
-    return {"symbols": symbols[:limit], "total_count": total, "returned_count": min(limit, total)}
-
-
-@mcp.tool()
-def list_examples(
-    category: str | None = None,
-    search: str | None = None,
-    limit: int = 50,
-) -> dict:
-    """List example circuits from LTspice examples library.
-
-    Args:
-        category: Filter by category folder
-        search: Search term for example name
-        limit: Maximum results to return
-    """
-    examples = []
-
-    if not LTSPICE_EXAMPLES.exists():
-        return {"error": "Examples not found", "examples": [], "total_count": 0}
-
-    for asc_file in LTSPICE_EXAMPLES.rglob("*.asc"):
-        rel_path = asc_file.relative_to(LTSPICE_EXAMPLES)
-        cat = str(rel_path.parent) if rel_path.parent != Path(".") else "misc"
-        name = asc_file.stem
-
-        if category and cat.lower() != category.lower():
-            continue
-        if search and search.lower() not in name.lower():
-            continue
-
-        examples.append({"name": name, "category": cat, "path": str(asc_file)})
-
-    examples.sort(key=lambda x: x["name"].lower())
-    total = len(examples)
-    return {"examples": examples[:limit], "total_count": total, "returned_count": min(limit, total)}
-
-
-@mcp.tool()
-def get_symbol_info(symbol_path: str) -> dict:
-    """Get detailed information about a component symbol.
-
-    Reads the .asy file to extract pin names, attributes, and description.
-
-    Args:
-        symbol_path: Path to .asy symbol file
-    """
-    path = Path(symbol_path)
-    if not path.exists():
-        return {"error": f"Symbol not found: {symbol_path}"}
-
-    content = path.read_text(errors="replace")
-    lines = content.split("\n")
-
-    info = {
-        "name": path.stem,
-        "pins": [],
-        "attributes": {},
-        "description": "",
-        "prefix": "",
-        "spice_prefix": "",
-    }
-
-    for line in lines:
-        line = line.strip()
-
-        if line.startswith("PIN"):
-            parts = line.split()
-            if len(parts) >= 5:
-                info["pins"].append(
-                    {
-                        "x": int(parts[1]),
-                        "y": int(parts[2]),
-                        "justification": parts[3],
-                        "rotation": parts[4] if len(parts) > 4 else "0",
-                    }
-                )
-
-        elif line.startswith("PINATTR PinName"):
-            pin_name = line.split(None, 2)[2] if len(line.split()) > 2 else ""
-            if info["pins"]:
-                info["pins"][-1]["name"] = pin_name
-
-        elif line.startswith("SYMATTR"):
-            parts = line.split(None, 2)
-            if len(parts) >= 3:
-                attr_name = parts[1]
-                attr_value = parts[2]
-                info["attributes"][attr_name] = attr_value
-                if attr_name == "Description":
-                    info["description"] = attr_value
-                elif attr_name == "Prefix":
-                    info["prefix"] = attr_value
-                elif attr_name == "SpiceModel":
-                    info["spice_prefix"] = attr_value
-
-    return info
-
-
-@mcp.tool()
-def search_spice_models(
-    search: str | None = None,
-    model_type: str | None = None,
-    limit: int = 50,
-) -> dict:
-    """Search for SPICE .model definitions in the library.
-
-    Finds transistors, diodes, and other discrete devices.
-
-    Args:
-        search: Search term for model name (case-insensitive)
-        model_type: Filter by type: NPN, PNP, NMOS, PMOS, D, NJF, PJF
-        limit: Maximum results
-    """
-    models = _search_models(search=search, model_type=model_type, limit=limit)
-    return {
-        "models": [
-            {
-                "name": m.name,
-                "type": m.type,
-                "source_file": m.source_file,
-                "parameters": m.parameters,
-            }
-            for m in models
-        ],
-        "total_count": len(models),
-    }
-
-
-@mcp.tool()
-def search_spice_subcircuits(
-    search: str | None = None,
-    limit: int = 50,
-) -> dict:
-    """Search for SPICE .subckt definitions (op-amps, ICs, etc.).
-
-    Args:
-        search: Search term for subcircuit name
-        limit: Maximum results
-    """
-    subs = _search_subcircuits(search=search, limit=limit)
-    return {
-        "subcircuits": [
-            {
-                "name": s.name,
-                "pins": s.pins,
-                "pin_names": s.pin_names,
-                "description": s.description,
-                "source_file": s.source_file,
-                "n_components": s.n_components,
-            }
-            for s in subs
-        ],
-        "total_count": len(subs),
-    }
-
-
-@mcp.tool()
-def check_installation() -> dict:
-    """Verify LTspice and Wine are properly installed."""
-    ok, msg = validate_installation()
-    from .config import LTSPICE_DIR, LTSPICE_EXE, WINE_PREFIX
-
-    return {
-        "valid": ok,
-        "message": msg,
-        "paths": {
-            "ltspice_dir": str(LTSPICE_DIR),
-            "ltspice_exe": str(LTSPICE_EXE),
-            "wine_prefix": str(WINE_PREFIX),
-            "lib_dir": str(LTSPICE_LIB),
-            "examples_dir": str(LTSPICE_EXAMPLES),
-        },
-        "lib_exists": LTSPICE_LIB.exists(),
-        "examples_exist": LTSPICE_EXAMPLES.exists(),
-    }
-
-
-# ============================================================================
-# RESOURCES
-# ============================================================================
-
-
-@mcp.resource("ltspice://symbols")
-def resource_symbols() -> str:
-    """All available LTspice symbols organized by category."""
-    result = list_symbols(limit=10000)
-    return json.dumps(result, indent=2)
-
-
-@mcp.resource("ltspice://examples")
-def resource_examples() -> str:
-    """All LTspice example circuits."""
-    result = list_examples(limit=10000)
-    return json.dumps(result, indent=2)
-
-
-@mcp.resource("ltspice://status")
-def resource_status() -> str:
-    """Current LTspice installation status."""
-    return json.dumps(check_installation(), indent=2)
-
-
-@mcp.resource("ltspice://templates")
-def resource_templates() -> str:
-    """All available circuit templates (netlist and schematic) with parameters."""
-    templates = {
-        "netlist_templates": [
-            {"name": name, "description": info["description"], "params": info["params"]}
-            for name, info in NETLIST_TEMPLATES.items()
-        ],
-        "schematic_templates": [
-            {"name": name, "description": info["description"], "params": info["params"]}
-            for name, info in ASC_TEMPLATES.items()
-        ],
-    }
-    return json.dumps(templates, indent=2)
-
-
-@mcp.resource("ltspice://template/{name}")
-def resource_template_detail(name: str) -> str:
-    """Detailed information about a specific circuit template."""
-    # Check both registries
-    netlist_info = NETLIST_TEMPLATES.get(name)
-    asc_info = ASC_TEMPLATES.get(name)
-
-    if not netlist_info and not asc_info:
-        return json.dumps({"error": f"Template '{name}' not found"})
-
-    result = {"name": name}
-    if netlist_info:
-        result["netlist"] = {
-            "description": netlist_info["description"],
-            "params": netlist_info["params"],
-            "type": "netlist (.cir)",
-        }
-    if asc_info:
-        result["schematic"] = {
-            "description": asc_info["description"],
-            "params": asc_info["params"],
-            "type": "schematic (.asc)",
-        }
-
-    return json.dumps(result, indent=2)
-
-
 # ============================================================================
 # PROMPTS
 # ============================================================================

tests/test_resources.py

@@ -0,0 +1,59 @@
+"""Resource-read regression tests.
+
+ltspice://symbols, ltspice://examples, and ltspice://status previously raised
+TypeError on read because the resource functions called @mcp.tool()-decorated
+names (FunctionTool objects are not callable). These tests read every resource
+to guard against that regressing.
+"""
+
+import inspect
+import json
+
+from mcltspice.library_tools import (
+    check_installation_impl,
+    list_examples_impl,
+    list_symbols_impl,
+)
+from mcltspice.server import mcp  # importing registers all resources
+
+
+async def _read(uri: str) -> str:
+    resources = await mcp.get_resources()
+    assert uri in resources, f"{uri} not registered"
+    out = resources[uri].fn()
+    if inspect.isawaitable(out):
+        out = await out
+    return out
+
+
+class TestResourceReadsWithoutError:
+    async def test_symbols_resource_reads(self):
+        out = await _read("ltspice://symbols")
+        json.loads(out)  # valid JSON, no TypeError
+
+    async def test_examples_resource_reads(self):
+        out = await _read("ltspice://examples")
+        json.loads(out)
+
+    async def test_status_resource_reads(self):
+        out = await _read("ltspice://status")
+        data = json.loads(out)
+        assert "valid" in data
+
+    async def test_templates_resource_reads(self):
+        out = await _read("ltspice://templates")
+        data = json.loads(out)
+        assert "netlist_templates" in data and "schematic_templates" in data
+
+
+class TestLibraryImplsAreCallable:
+    """The fix: the *_impl functions must be plain callables (not FunctionTool)."""
+
+    def test_impls_are_callable(self):
+        assert callable(list_symbols_impl)
+        assert callable(list_examples_impl)
+        assert callable(check_installation_impl)
+
+    def test_check_installation_impl_shape(self):
+        result = check_installation_impl()
+        assert set(result) >= {"valid", "message", "paths", "lib_exists"}