Widthdom · Widthdom · May 31, 2026 · May 31, 2026 · May 31, 2026 · May 31, 2026
diff --git a/changelog.d/unreleased/1415.fixed.md b/changelog.d/unreleased/1415.fixed.md
@@ -0,0 +1,13 @@
+---
+category: fixed
+issues:
+  - 1415
+---
+
+## English
+
+- Confirmed MCP `references`, `callers`, and `callees` expose truncation metadata when a result page reaches the requested limit.
+
+## 日本語
+
+- MCP `references`、`callers`、`callees` が要求 limit に達した結果ページで truncation metadata を返すことを確認しました。
diff --git a/changelog.d/unreleased/1595.changed.md b/changelog.d/unreleased/1595.changed.md
@@ -0,0 +1,13 @@
+---
+category: changed
+issues:
+  - 1595
+---
+
+## English
+
+- Centralized query limit defaults so CLI and MCP defaults are reviewable from shared constants.
+
+## 日本語
+
+- CLI と MCP の query limit 既定値を共有定数へ集約し、既定値をレビューしやすくしました。
diff --git a/changelog.d/unreleased/1605.fixed.md b/changelog.d/unreleased/1605.fixed.md
@@ -0,0 +1,13 @@
+---
+category: fixed
+issues:
+  - 1605
+---
+
+## English
+
+- Added an MCP `excerpt` output byte cap that truncates content at line boundaries and reports `truncated` with `truncation_reason: output_size_cap`.
+
+## 日本語
+
+- MCP `excerpt` に出力 byte 上限を追加し、行境界で content を切り詰めて `truncated` と `truncation_reason: output_size_cap` を返すようにしました。
diff --git a/src/CodeIndex/Cli/QueryCommandRunner.cs b/src/CodeIndex/Cli/QueryCommandRunner.cs
@@ -17,6 +17,9 @@ namespace CodeIndex.Cli;
 /// </summary>
 public static class QueryCommandRunner
 {
+    internal const int DefaultQueryLimit = 20;
+    internal const int DefaultMapLimit = 10;
+    internal const int DefaultImpactLimit = 50;
     internal const string DefaultLimitEnvironmentVariable = "CDIDX_DEFAULT_LIMIT";
     internal const string DefaultSnippetLinesEnvironmentVariable = "CDIDX_DEFAULT_SNIPPET_LINES";
     internal const string DefaultMaxLineWidthEnvironmentVariable = "CDIDX_DEFAULT_MAX_LINE_WIDTH";
@@ -4552,7 +4555,7 @@ public static QueryCommandOptions ParseArgs(
         string? dataDir = null;
         bool? json = null;
         string jsonOutputFormat = JsonOutputFormatNdjson;
-        int limit = ResolveDefaultPositiveInt(DefaultLimitEnvironmentVariable, 20, "--limit", out var defaultLimitError);
+        int limit = ResolveDefaultPositiveInt(DefaultLimitEnvironmentVariable, DefaultQueryLimit, "--limit", out var defaultLimitError);
         string? lang = null;
         string? kind = null;
         string? query = null;

diff --git a/src/CodeIndex/Mcp/McpToolDefinitions.cs b/src/CodeIndex/Mcp/McpToolDefinitions.cs
diff --git a/src/CodeIndex/Mcp/McpToolHandlers.cs b/src/CodeIndex/Mcp/McpToolHandlers.cs
@@ -18,6 +18,7 @@ namespace CodeIndex.Mcp;
 public partial class McpServer
 {
     private const int DefaultBatchQueryResponseByteLimit = MaxLineByteLength;
+    private const int DefaultExcerptOutputByteLimit = MaxLineByteLength;
     private const string BatchQueryResponseByteLimitEnvVar = "CDIDX_MCP_BATCH_RESPONSE_MAX_BYTES";
     internal const int MaxMcpArrayFilterCount = 100;
     internal const int MaxMcpArrayFilterStringLength = 4096;
@@ -815,7 +816,7 @@ private JsonNode ExecuteSearch(JsonNode? id, JsonNode? args)
         if (query.Length > QueryLimits.MaxQueryLength)
             return CreateToolErrorResponse(id, QueryLimits.FormatQueryTooLongError());
 
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 20);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultQueryLimit);
         var lang = QueryCommandRunner.NormalizeLangFilterValue(args?["lang"]?.GetValue<string>());
         var snippetLines = SearchSnippetFormatter.ClampSnippetLines(args?["snippetLines"]?.GetValue<int>() ?? SearchSnippetFormatter.DefaultSnippetLines);
         if (TryGetValidatedMaxLineWidth(id, args, out var maxLineWidth) is JsonNode maxLineWidthError)
@@ -935,7 +936,7 @@ private JsonNode ExecuteSymbols(JsonNode? id, JsonNode? args)
             return CreateToolErrorResponse(id, "'names' is present but contains no usable entries (all were empty or whitespace).");
         var kind = args?["kind"]?.GetValue<string>()?.ToLowerInvariant();
         var lang = QueryCommandRunner.NormalizeLangFilterValue(args?["lang"]?.GetValue<string>());
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 20);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultQueryLimit);
         if (TryGetValidatedMaxLineWidth(id, args, out var maxLineWidth) is JsonNode maxLineWidthError)
             return maxLineWidthError;
         var pathPatterns = ReadScopedPathList(args);
@@ -1030,7 +1031,7 @@ private JsonNode ExecuteDefinition(JsonNode? id, JsonNode? args)
 
         var kind = args?["kind"]?.GetValue<string>()?.ToLowerInvariant();
         var lang = QueryCommandRunner.NormalizeLangFilterValue(args?["lang"]?.GetValue<string>());
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 20);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultQueryLimit);
         var includeBody = args?["includeBody"]?.GetValue<bool>() ?? false;
         var lspCompatible = args?["lsp_compatible"]?.GetValue<bool>() ?? false;
         var pathPatterns = ReadScopedPathList(args);
@@ -1111,7 +1112,7 @@ private JsonNode ExecuteReferences(JsonNode? id, JsonNode? args)
 
         var kind = args?["kind"]?.GetValue<string>()?.ToLowerInvariant();
         var lang = QueryCommandRunner.NormalizeLangFilterValue(args?["lang"]?.GetValue<string>());
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 20);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultQueryLimit);
         var lspCompatible = args?["lsp_compatible"]?.GetValue<bool>() ?? false;
         var offset = ReadOffset(args);
         if (TryGetValidatedMaxLineWidth(id, args, out var maxLineWidth) is JsonNode maxLineWidthError)
@@ -1216,7 +1217,7 @@ private JsonNode ExecuteCallers(JsonNode? id, JsonNode? args)
         if (IsNonCallGraphReferenceKind(kind))
             return CreateToolErrorResponse(id, BuildNonCallGraphKindRejectionMessage("callers", kind!));
         var lang = QueryCommandRunner.NormalizeLangFilterValue(args?["lang"]?.GetValue<string>());
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 20);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultQueryLimit);
         var offset = ReadOffset(args);
         var pathPatterns = ReadScopedPathList(args);
         var excludePaths = ReadStringList(args, "excludePaths");
@@ -1310,7 +1311,7 @@ private JsonNode ExecuteCallees(JsonNode? id, JsonNode? args)
         if (IsNonCallGraphReferenceKind(kind))
             return CreateToolErrorResponse(id, BuildNonCallGraphKindRejectionMessage("callees", kind!));
         var lang = QueryCommandRunner.NormalizeLangFilterValue(args?["lang"]?.GetValue<string>());
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 20);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultQueryLimit);
         var offset = ReadOffset(args);
         var pathPatterns = ReadScopedPathList(args);
         var excludePaths = ReadStringList(args, "excludePaths");
@@ -1397,7 +1398,7 @@ private JsonNode ExecuteFiles(JsonNode? id, JsonNode? args)
         if (query != null && query.Length > QueryLimits.MaxQueryLength)
             return CreateToolErrorResponse(id, QueryLimits.FormatQueryTooLongError());
         var lang = QueryCommandRunner.NormalizeLangFilterValue(args?["lang"]?.GetValue<string>());
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 20);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultQueryLimit);
         var pathPatterns = ReadScopedPathList(args);
         var excludePaths = ReadStringList(args, "excludePaths");
         var excludeTests = args?["excludeTests"]?.GetValue<bool>() ?? false;
@@ -1445,7 +1446,7 @@ private JsonNode ExecuteFiles(JsonNode? id, JsonNode? args)
     private JsonNode ExecuteMap(JsonNode? id, JsonNode? args)
     {
         var lang = args?["lang"]?.GetValue<string>()?.ToLowerInvariant();
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 10);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultMapLimit);
         var pathPatterns = ReadScopedPathList(args);
         var excludePaths = ReadStringList(args, "excludePaths");
         var excludeTests = args?["excludeTests"]?.GetValue<bool>() ?? false;
@@ -1478,7 +1479,7 @@ private JsonNode ExecuteAnalyzeSymbol(JsonNode? id, JsonNode? args)
         if (IsBareVerbatimQueryToken(query))
             return CreateToolErrorResponse(id, "Add a real symbol name after the command; bare verbatim prefixes like `@` are not valid queries.");
 
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 10);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultMapLimit);
         var lang = args?["lang"]?.GetValue<string>()?.ToLowerInvariant();
         var includeBody = args?["includeBody"]?.GetValue<bool>() ?? false;
         if (TryGetValidatedMaxLineWidth(id, args, out var maxLineWidth) is JsonNode maxLineWidthError)
@@ -1877,6 +1878,8 @@ private JsonNode ExecuteExcerpt(JsonNode? id, JsonNode? args)
         var explicitFocusLength = args?["focusLength"] != null;
         if (TryGetValidatedMaxLineWidth(id, args, out var maxLineWidth) is JsonNode maxLineWidthError)
             return maxLineWidthError;
+        if (!TryReadMaxOutputBytes(args, out var maxOutputBytes, out var maxOutputBytesError))
+            return CreateToolErrorResponse(id, maxOutputBytesError!);
 
         if (focusLine.HasValue && focusLine.Value <= 0)
             return CreateToolErrorResponse(id, "focusLine must be greater than or equal to 1");
@@ -1937,6 +1940,8 @@ private JsonNode ExecuteExcerpt(JsonNode? id, JsonNode? args)
             }
 
             var payload = JsonSerializer.SerializeToNode(excerpt, _jsonOptions)!.AsObject();
+            ApplyExcerptOutputBudget(payload, maxOutputBytes);
+            payload["maxOutputBytes"] = maxOutputBytes;
             payload["before"] = before;
             payload["after"] = after;
             payload["contextTruncated"] = contextTruncated;
@@ -1954,6 +1959,45 @@ private JsonNode ExecuteExcerpt(JsonNode? id, JsonNode? args)
         });
     }
 
+    private static bool TryReadMaxOutputBytes(JsonNode? args, out int maxOutputBytes, out string? error)
+    {
+        maxOutputBytes = DefaultExcerptOutputByteLimit;
+        error = null;
+        if (args?["maxOutputBytes"] is not JsonNode node)
+            return true;
+        var requested = node.GetValue<int>();
+        if (requested <= 0)
+        {
+            error = "maxOutputBytes must be greater than or equal to 1";
+            return false;
+        }
+        maxOutputBytes = Math.Min(requested, DefaultExcerptOutputByteLimit);
+        return true;
+    }
+
+    internal static void ApplyExcerptOutputBudget(JsonObject payload, int maxOutputBytes)
+    {
+        var contentKey = payload.ContainsKey("content") ? "content" : "Content";
+        if (payload[contentKey]?.GetValue<string>() is not string content)
+            return;
+        if (Encoding.UTF8.GetByteCount(content) <= maxOutputBytes)
+            return;
+
+        var builder = new StringBuilder();
+        foreach (var line in content.Replace("\r\n", "\n").Split('\n'))
+        {
+            var candidate = builder.Length == 0 ? line : builder.ToString() + "\n" + line;
+            if (Encoding.UTF8.GetByteCount(candidate) > maxOutputBytes)
+                break;
+            builder.Clear();
+            builder.Append(candidate);
+        }
+        payload[contentKey] = builder.ToString();
+        payload["contentTruncated"] = true;
+        payload["truncated"] = true;
+        payload["truncation_reason"] = "output_size_cap";
+    }
+
     private JsonNode ExecuteFindInFile(JsonNode? id, JsonNode? args)
     {
         if (!TryReadRequiredStringParameter(args, "query", out var query, out var requiredError))
@@ -1967,7 +2011,7 @@ private JsonNode ExecuteFindInFile(JsonNode? id, JsonNode? args)
                 ? "Parameter \"path\" cannot be empty or whitespace-only"
                 : "Missing required parameter: path");
 
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 20);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultQueryLimit);
         var lang = args?["lang"]?.GetValue<string>()?.ToLowerInvariant();
         var excludePaths = ReadStringList(args, "excludePaths");
         var excludeTests = args?["excludeTests"]?.GetValue<bool>() ?? false;
@@ -2536,7 +2580,7 @@ private static string BuildArgsSummary(JsonNode? toolArgs)
 
     private JsonNode ExecuteDeps(JsonNode? id, JsonNode? args)
     {
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 50);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultImpactLimit);
         var lang = args?["lang"]?.GetValue<string>()?.ToLowerInvariant();
         var pathPatterns = ReadScopedPathList(args);
         var excludePaths = ReadStringList(args, "excludePaths");
@@ -2581,7 +2625,7 @@ private JsonNode ExecuteImpactAnalysis(JsonNode? id, JsonNode? args)
         var usedDeprecatedMaxDepth = deprecatedMaxDepthNode != null;
         var maxDepthRequested = maxHopsNode?.GetValue<int>() ?? deprecatedMaxDepthNode?.GetValue<int>() ?? 5;
         var maxDepth = Math.Clamp(maxDepthRequested, 0, MaxImpactDepth);
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 50);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultImpactLimit);
         var lang = args?["lang"]?.GetValue<string>()?.ToLowerInvariant();
         var pathPatterns = ReadScopedPathList(args);
         var excludePaths = ReadStringList(args, "excludePaths");
@@ -2756,7 +2800,7 @@ private JsonNode ExecuteValidate(JsonNode? id, JsonNode? args)
 
     private JsonNode ExecuteSymbolHotspots(JsonNode? id, JsonNode? args)
     {
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 20);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultQueryLimit);
         var kind = args?["kind"]?.GetValue<string>()?.ToLowerInvariant();
         var lang = args?["lang"]?.GetValue<string>()?.ToLowerInvariant();
         var groupBy = args?["groupBy"]?.GetValue<string>()?.ToLowerInvariant()
@@ -2868,7 +2912,7 @@ private JsonNode ExecuteSymbolHotspots(JsonNode? id, JsonNode? args)
 
     private JsonNode ExecuteUnusedSymbols(JsonNode? id, JsonNode? args)
     {
-        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? 50);
+        var limit = ClampLimit(args?["limit"]?.GetValue<int>() ?? QueryCommandRunner.DefaultImpactLimit);
         var kind = args?["kind"]?.GetValue<string>()?.ToLowerInvariant();
         var lang = args?["lang"]?.GetValue<string>()?.ToLowerInvariant();
         var pathPatterns = ReadScopedPathList(args);

diff --git a/tests/CodeIndex.Tests/McpServerTests.cs b/tests/CodeIndex.Tests/McpServerTests.cs
@@ -258,6 +258,37 @@ void Target() { }
         Assert.Contains("Gamma", allNames);
     }
 
+    [Theory]
+    [InlineData("references", "Target")]
+    [InlineData("callees", "Source")]
+    public void ToolsCall_GraphTools_TruncatedResponseIncludesEnvelope_Issue1415(string tool, string query)
+    {
+        InsertIndexedFile(
+            "src/paged-graph.cs",
+            "csharp",
+            """
+            class PagedGraph {
+                void Source() { Alpha(); Beta(); Gamma(); }
+                void Alpha() { Target(); }
+                void Beta() { Target(); }
+                void Gamma() { Target(); }
+                void Target() { }
+            }
+            """);
+
+        var request = JsonNode.Parse(
+            """{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"TOOL","arguments":{"query":"Target","lang":"csharp","exactName":true,"path":"src/paged-graph.cs","limit":2}}}"""
+                .Replace("TOOL", tool, StringComparison.Ordinal)
+                .Replace("Target", query, StringComparison.Ordinal))!;
+        var response = _server.HandleMessage(request)!;
+        var structured = response["result"]!["structuredContent"]!;
+
+        Assert.Equal(2, structured["count"]!.GetValue<int>());
+        Assert.True(structured["truncated"]!.GetValue<bool>());
+        Assert.True(structured["more_available"]!.GetValue<bool>());
+        Assert.Equal(2, structured["next_offset"]!.GetValue<int>());
+    }
+
     [Fact]
     public void ToolsCall_Search_WithResultsIncludesNextStepSuggestion()
     {
@@ -6449,6 +6480,23 @@ public void ToolsCall_BatchQuery_TruncatesAggregateResponse_Issue1416()
         }
     }
 
+    [Fact]
+    public void ApplyExcerptOutputBudget_TruncatesAtLineBoundary_Issue1605()
+    {
+        var payload = new JsonObject
+        {
+            ["content"] = "short\n" + new string('x', 200),
+            ["contentTruncated"] = false,
+        };
+
+        McpServer.ApplyExcerptOutputBudget(payload, 20);
+
+        Assert.True(payload["truncated"]!.GetValue<bool>());
+        Assert.Equal("output_size_cap", payload["truncation_reason"]!.GetValue<string>());
+        Assert.Equal("short", payload["content"]!.GetValue<string>());
+        Assert.True(payload["contentTruncated"]!.GetValue<bool>());
+    }
+
     [Fact]
     public void ToolsCall_BatchQuery_ArgsSummaryReflectsRequestedArguments_Issue1537()
     {