feat: add JSON output

src/semble/cli.py

@@ -1,5 +1,6 @@
 import argparse
 import asyncio
+import json
 import sys
 import warnings
 from enum import Enum
@@ -185,9 +186,10 @@ def _cli_main() -> None:
     if args.command == "search":
         results = index.search(args.query, top_k=args.top_k)
         if not results:
-            print("No results found.")
+            out = {"error": "No results found."}
         else:
-            print(format_results(f"Search results for: {args.query!r}", results))
+            out = format_results(args.query, results)
+        print(json.dumps(out))
 
     elif args.command == "find-related":
         chunk = resolve_chunk(index.chunks, args.file_path, args.line)
@@ -196,6 +198,7 @@ def _cli_main() -> None:
             sys.exit(1)
         results = index.find_related(chunk, top_k=args.top_k)
         if not results:
-            print(f"No related chunks found for {args.file_path}:{args.line}.")
+            out = {"error": f"No related chunks found for {args.file_path}:{args.line}."}
         else:
-            print(format_results(f"Chunks related to {args.file_path}:{args.line}", results))
+            out = format_results(f"Chunks related to {args.file_path}:{args.line}", results)
+        print(json.dumps(out))

src/semble/mcp.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import asyncio
+import json
 import logging
 from collections import OrderedDict
 from collections.abc import Sequence
@@ -77,8 +78,8 @@ async def search(
             return str(exc)
         results = index.search(query, top_k=top_k)
         if not results:
-            return "No results found."
-        return format_results(f"Search results for: {query!r}", results)
+            return json.dumps({"error": "No results found."})
+        return json.dumps(format_results(query, results))
 
     @server.tool()
     async def find_related(
@@ -107,8 +108,8 @@ async def find_related(
             )
         results = index.find_related(chunk, top_k=top_k)
         if not results:
-            return f"No related chunks found for {file_path}:{line}."
-        return format_results(f"Chunks related to {file_path}:{line}", results)
+            return json.dumps({"error": f"No related chunks found for {file_path}:{line}."})
+        return json.dumps(format_results(f"Chunks related to {file_path}:{line}", results))
 
     return server
 

src/semble/types.py

@@ -42,11 +42,14 @@ def location(self) -> str:
 
     def to_dict(self) -> dict[str, Any]:
         """Convert the dataclass to a dict."""
-        return asdict(self)
+        d = asdict(self)
+        d["location"] = self.location
+        return d
 
     @classmethod
     def from_dict(cls: type[Chunk], data: dict[str, Any]) -> Chunk:
         """Create a Chunk from a dict."""
+        data.pop("location", None)
         return cls(**data)
 
 
@@ -57,6 +60,13 @@ class SearchResult:
     chunk: Chunk
     score: float
 
+    def to_dict(self) -> dict[str, Any]:
+        """Dump a search result to a dict."""
+        return {
+            "chunk": self.chunk.to_dict(),
+            "score": self.score,
+        }
+
 
 @dataclass(frozen=True, slots=True)
 class IndexStats:

src/semble/utils.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import re
+from typing import Any
 
 from semble.types import Chunk, SearchResult
 
@@ -29,13 +30,6 @@ def resolve_chunk(chunks: list[Chunk], file_path: str, line: int) -> Chunk | Non
     return fallback
 
 
-def format_results(header: str, results: list[SearchResult]) -> str:
-    """Render SearchResult objects as numbered, fenced code blocks."""
-    lines: list[str] = [header, ""]
-    for i, r in enumerate(results, 1):
-        lines.append(f"## {i}. {r.chunk.location}  [score={r.score:.3f}]")
-        lines.append("```")
-        lines.append(r.chunk.content.strip())
-        lines.append("```")
-        lines.append("")
-    return "\n".join(lines)
+def format_results(query: str, results: list[SearchResult]) -> dict[str, Any]:
+    """Render SearchResult objects as a JSONable object."""
+    return {"query": query, "results": [r.to_dict() for r in results]}

tests/test_cli.py

@@ -57,7 +57,7 @@ def test_cli_search(
 @pytest.mark.parametrize(
     ("scenario", "expected_stdout", "expected_stderr", "expected_exit_code"),
     [
-        ("with_results", ["src/bar.py", "0.800"], None, None),
+        ("with_results", ["src/bar.py", "0.8"], None, None),
         ("no_results", ["No related chunks found"], None, None),
         ("unknown_chunk", [], "No chunk found", 1),
     ],

tests/test_mcp.py

@@ -88,19 +88,19 @@ def test_is_git_url(path: str, expected: bool) -> None:
 
 def test_format_results() -> None:
     """_format_results: empty list → header only; with results → numbered fenced blocks with scores."""
-    empty_out = format_results("My header", [])
-    assert "My header" in empty_out
-    assert "```" not in empty_out
+    empty_out = format_results("query", [])
+    assert empty_out == {"query": "query", "results": []}
 
     chunks = [make_chunk(f"def fn_{i}(): pass", f"f{i}.py") for i in range(3)]
     results = [SearchResult(chunk=c, score=round(0.1 * (i + 1), 3)) for i, c in enumerate(chunks)]
-    out = format_results("Results for: 'foo'", results)
-    assert "Results for: 'foo'" in out
-    assert out.count("```") >= len(results) * 2  # opening + closing fence each
-    for i, c in enumerate(chunks, start=1):
-        assert f"## {i}." in out
-        assert c.content in out
-    assert "0.100" in out and "0.200" in out and "0.300" in out
+    out = format_results("foo", results)
+    assert out["query"] == "foo"
+    contents = set(x["chunk"]["content"] for x in out["results"])
+    scores = set(x["score"] for x in out["results"])
+    for chunk in chunks:
+        assert chunk.content in contents
+    for score in [0.1, 0.2, 0.3]:
+        assert score in scores
 
 
 @pytest.mark.anyio
@@ -189,7 +189,7 @@ async def test_tool_index_failure(cache: _IndexCache, tool: str, args: dict[str,
             "search",
             [SearchResult(chunk=make_chunk("def bar(): pass", "src/bar.py"), score=0.9)],
             None,
-            ["bar", "0.900"],
+            ["bar", "0.9"],
             id="search_with_results",
         ),
         pytest.param(
@@ -207,7 +207,7 @@ async def test_tool_index_failure(cache: _IndexCache, tool: str, args: dict[str,
             "find_related",
             [SearchResult(chunk=make_chunk("class Foo: pass", "src/foo.py"), score=0.8)],
             [make_chunk("class Foo: pass", "src/foo.py")],
-            ["src/foo.py:1", "0.800"],
+            ["src/foo.py:1", "0.8"],
             id="find_related_with_results",
         ),
         pytest.param(