feat(tools): compress tool schemas and truncate descriptions

kiro/config.py

@@ -297,6 +297,20 @@ def _get_raw_env_value(var_name: str, env_file: str = ".env") -> Optional[str]:
 # Set to 0 to disable (not recommended - will cause Kiro API errors).
 TOOL_DESCRIPTION_MAX_LENGTH: int = int(os.getenv("TOOL_DESCRIPTION_MAX_LENGTH", "10000"))
 
+# ==================================================================================================
+# Tool Schema Compression
+# ==================================================================================================
+
+# Strip verbose fields (description, title, examples, $comment) from tool input schemas.
+# Reduces token usage significantly when many MCP tools are present.
+# Default: true (enabled)
+KIRO_COMPRESS_TOOL_SCHEMAS: bool = os.getenv("KIRO_COMPRESS_TOOL_SCHEMAS", "true").lower() in ("true", "1", "yes")
+
+# Maximum characters for tool descriptions. Longer descriptions are truncated.
+# Set to 0 to disable truncation.
+# Default: 200
+KIRO_TOOL_DESC_MAX_CHARS: int = int(os.getenv("KIRO_TOOL_DESC_MAX_CHARS", "200"))
+
 # ==================================================================================================
 # Truncation Recovery Settings
 # ==================================================================================================

kiro/converters_core.py

@@ -533,29 +533,82 @@ def validate_tool_names(tools: Optional[List[UnifiedTool]]) -> None:
         )
 
 
+def compress_json_schema(schema: Dict[str, Any]) -> Dict[str, Any]:
+    """
+    Strips verbose fields from JSON Schema properties recursively.
+
+    Removes description, title, examples, $comment, and markdownDescription,
+    keeping only structural fields needed for tool call generation.
+
+    Args:
+        schema: JSON Schema dictionary to compress.
+
+    Returns:
+        New dictionary with verbose fields removed.
+    """
+    if not schema:
+        return {}
+
+    STRIP_KEYS = {"description", "title", "examples", "$comment", "markdownDescription"}
+    result = {}
+
+    for key, value in schema.items():
+        if key in STRIP_KEYS:
+            continue
+        if key == "properties" and isinstance(value, dict):
+            result[key] = {
+                pn: compress_json_schema(pv) if isinstance(pv, dict) else pv
+                for pn, pv in value.items()
+            }
+        elif isinstance(value, dict):
+            result[key] = compress_json_schema(value)
+        elif isinstance(value, list):
+            result[key] = [
+                compress_json_schema(item) if isinstance(item, dict) else item
+                for item in value
+            ]
+        else:
+            result[key] = value
+
+    return result
+
+
 def convert_tools_to_kiro_format(tools: Optional[List[UnifiedTool]]) -> List[Dict[str, Any]]:
     """
     Converts unified tools to Kiro API format.
 
+    Optionally compresses tool schemas and truncates descriptions
+    based on KIRO_COMPRESS_TOOL_SCHEMAS and KIRO_TOOL_DESC_MAX_CHARS config.
+
     Args:
         tools: List of tools in unified format
 
     Returns:
         List of tools in Kiro toolSpecification format
     """
+    from kiro.config import KIRO_COMPRESS_TOOL_SCHEMAS, KIRO_TOOL_DESC_MAX_CHARS
+
     if not tools:
         return []
 
     kiro_tools = []
     for tool in tools:
         # Sanitize parameters from fields that Kiro API doesn't accept
         sanitized_params = sanitize_json_schema(tool.input_schema)
+
+        # Optionally compress schema to reduce token usage
+        if KIRO_COMPRESS_TOOL_SCHEMAS:
+            sanitized_params = compress_json_schema(sanitized_params)
 
         # Kiro API requires non-empty description
         description = tool.description
         if not description or not description.strip():
             description = f"Tool: {tool.name}"
             logger.debug(f"Tool '{tool.name}' has empty description, using placeholder")
+
+        # Optionally truncate long descriptions
+        if KIRO_TOOL_DESC_MAX_CHARS and description and len(description) > KIRO_TOOL_DESC_MAX_CHARS:
+            description = description[:KIRO_TOOL_DESC_MAX_CHARS] + "..."
 
         kiro_tools.append({
             "toolSpecification": {