perf(tools): lower default result sizes to cut response tokens

The default limits let broad queries flood the model context. This
change sets smaller defaults. An explicit parameter still overrides each one.

- file_search: max_results 1000 to 50, context_lines 2 to 0.
- ast_query: max_results 100 to 50.
- ast_query compact output omits the node type unless verbose is set.

On a fixed seven-call suite, response size fell from 198529 to 61960 bytes.

internal/server/handlers_ast.go

@@ -60,7 +60,7 @@ func (s *Server) resolveASTQueryParams(request mcp.CallToolRequest) (*astQueryPa
 		prefsMaxResults = sp.DefaultMaxResults
 		prefsFormat = sp.ASTQueryFormat
 	}
-	p.maxResults = effectiveInt(request, "max_results", prefsMaxResults, 100)
+	p.maxResults = effectiveInt(request, "max_results", prefsMaxResults, 50)
 
 	p.format = request.GetString("format", "")
 	if p.format == "" {

internal/server/handlers_file.go

@@ -51,7 +51,7 @@ func (s *Server) handleFileSearch(ctx context.Context, request mcp.CallToolReque
 	fileTypes := request.GetStringSlice("file_types", nil)
 	ignoreCase := request.GetBool("ignore_case", false)
 	regex := request.GetBool("regex", true)
-	contextLines := request.GetInt("context_lines", 2)
+	contextLines := request.GetInt("context_lines", 0)
 
 	// Consult session prefs for max_results and cluster when not explicitly supplied.
 	prefs := s.sessionPrefs.Load()

internal/server/help_content.go

@@ -49,7 +49,7 @@ const helpFileSearch = "# file_search — flags and examples\n\n" +
 	"| `cluster=true` | Coalesce consecutive match lines into ranges (`L12-14│ text`). Drops context lines for density. |\n" +
 	"| `cursor` | Opaque pagination token from a previous truncated response — fetches next page. |\n" +
 	"| `max_results` | Page size for pagination. Re-run with `cursor` to get next page. |\n" +
-	"| `context_lines` | Number of context lines around matches (default: 2). |\n" +
+	"| `context_lines` | Number of context lines around matches (default: 0). |\n" +
 	"| `ignore_case` | Case-insensitive search. |\n" +
 	"| `regex` | Treat pattern as regex (default: true). |\n" +
 	"| `file_types` | Restrict to file extensions, e.g. `[\"go\", \"ts\"]`. |\n" +
@@ -77,7 +77,7 @@ const helpASTQuery = "# ast_query — flags and examples\n\n" +
 	"| `verbose=true` | Emit `Found N match(es):` preamble (v1 behaviour). Default: false. |\n" +
 	"| `format` | `compact` (default, one line per match) \\| `verbose` (full code+captures) \\| `location` (file:line only) |\n" +
 	"| `cursor` | Opaque pagination token from a previous truncated response — fetches next page. |\n" +
-	"| `max_results` | Page size (default: 100). |\n" +
+	"| `max_results` | Page size (default: 50). |\n" +
 	"| `name_exact` | Exact symbol name to match. |\n" +
 	"| `name_matches` | Regex pattern to filter by name. |\n" +
 	"| `kind_in` | Node types to match (e.g. `function_declaration`, `class_declaration`). |\n" +

internal/server/server.go

@@ -136,7 +136,7 @@ func (s *Server) registerTools() {
 					mcp.Description("Treat pattern as regex (default: true)"),
 				),
 				mcp.WithNumber("context_lines",
-					mcp.Description("Number of context lines around matches (default: 2)"),
+					mcp.Description("Number of context lines around matches (default: 0)"),
 				),
 				mcp.WithNumber("max_results",
 					mcp.Description("Maximum number of results to return (page size for pagination)"),
@@ -252,7 +252,7 @@ func (s *Server) registerTools() {
 				mcp.WithStringItems(),
 			),
 			mcp.WithNumber("max_results",
-				mcp.Description("Maximum number of results to return (default: 100, page size for pagination)"),
+				mcp.Description("Maximum number of results to return (default: 50, page size for pagination)"),
 			),
 			mcp.WithString("format",
 				mcp.Description("Output format: \"compact\" (default, one line per match), \"verbose\" (full code+captures), \"location\" (file:line only)"),