Warn about broad tool response projections

crates/crank-core/src/lib.rs

@@ -63,7 +63,9 @@ pub use operation::{
 pub use protocol::{AuthKind, ExportMode, HttpMethod, Protocol};
 pub use secret::{Secret, SecretKind, SecretStatus, SecretVersion};
 pub use tool_quality::{
-    ToolQualityFinding, ToolQualityReport, ToolQualitySchemaKind, ToolQualitySchemaNode,
-    ToolQualitySeverity, analyze_tool_identity_quality, analyze_tool_schema_quality,
+    ToolQualityFinding, ToolQualityMappingRule, ToolQualityMappingSet, ToolQualityReport,
+    ToolQualitySchemaKind, ToolQualitySchemaNode, ToolQualitySeverity,
+    analyze_tool_identity_quality, analyze_tool_response_projection_quality,
+    analyze_tool_schema_quality,
 };
 pub use workspace::{Workspace, WorkspaceStatus};

crates/crank-core/src/tool_quality.rs

@@ -7,6 +7,7 @@ const MIN_DESCRIPTION_CHARS: usize = 40;
 const GENERIC_TOOL_NAMES: &[&str] = &["call_api", "manage", "execute", "request"];
 const MULTI_ACTION_FIELD_NAMES: &[&str] = &["action", "mode", "operation", "type"];
 const ENUM_LIKE_FIELD_NAMES: &[&str] = &["mode", "type", "status", "category"];
+const MANY_PROJECTED_FIELDS_THRESHOLD: usize = 12;
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(rename_all = "snake_case")]
@@ -58,6 +59,17 @@ pub struct ToolQualitySchemaNode {
     pub enum_values: Vec<String>,
 }
 
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
+pub struct ToolQualityMappingRule {
+    pub source: String,
+    pub target: String,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, Default)]
+pub struct ToolQualityMappingSet {
+    pub rules: Vec<ToolQualityMappingRule>,
+}
+
 impl ToolQualityReport {
     pub fn new(findings: Vec<ToolQualityFinding>) -> Self {
         let blocking = findings
@@ -175,6 +187,37 @@ pub fn analyze_tool_schema_quality(
     ToolQualityReport::new(findings)
 }
 
+pub fn analyze_tool_response_projection_quality(
+    output_mapping: &ToolQualityMappingSet,
+) -> ToolQualityReport {
+    let mut findings = Vec::new();
+
+    for (index, rule) in output_mapping.rules.iter().enumerate() {
+        let source = rule.source.trim();
+        if source == "$.response.body" || source == "$.response.data" {
+            findings.push(finding(
+                ToolQualitySeverity::Warning,
+                "response_projection_full_body",
+                "Результат инструмента отдает агенту весь ответ API.",
+                Some("Выберите только поля, которые нужны агенту для ответа пользователю или следующего действия."),
+                Some(&format!("output_mapping.rules.{index}.source")),
+            ));
+        }
+    }
+
+    if output_mapping.rules.len() >= MANY_PROJECTED_FIELDS_THRESHOLD {
+        findings.push(finding(
+            ToolQualitySeverity::Info,
+            "response_projection_many_fields",
+            "В результат инструмента попадает много полей.",
+            Some("Проверьте, что каждое поле действительно нужно агенту. Лишние данные увеличивают риск ошибок и галлюцинаций."),
+            Some("output_mapping.rules"),
+        ));
+    }
+
+    ToolQualityReport::new(findings)
+}
+
 fn is_safe_tool_name(value: &str) -> bool {
     let mut chars = value.chars();
     let Some(first) = chars.next() else {

crates/crank-core/tests/unit/tool_quality.rs

@@ -1,6 +1,7 @@
 use crank_core::{
-    ToolDescription, ToolQualityFinding, ToolQualityReport, ToolQualitySchemaNode,
-    ToolQualitySeverity, analyze_tool_identity_quality, analyze_tool_schema_quality,
+    ToolDescription, ToolQualityFinding, ToolQualityMappingRule, ToolQualityMappingSet,
+    ToolQualityReport, ToolQualitySchemaNode, ToolQualitySeverity, analyze_tool_identity_quality,
+    analyze_tool_response_projection_quality, analyze_tool_schema_quality,
 };
 
 #[test]
@@ -181,6 +182,59 @@ fn recommends_enum_for_mode_like_string_parameter() {
     ));
 }
 
+#[test]
+fn warns_when_output_mapping_returns_full_response_body() {
+    let mapping = ToolQualityMappingSet {
+        rules: vec![ToolQualityMappingRule {
+            source: "$.response.body".to_owned(),
+            target: "$.output".to_owned(),
+        }],
+    };
+
+    let report = analyze_tool_response_projection_quality(&mapping);
+
+    assert!(has_finding(
+        &report,
+        "response_projection_full_body",
+        ToolQualitySeverity::Warning
+    ));
+}
+
+#[test]
+fn accepts_output_mapping_with_selected_fields() {
+    let mapping = ToolQualityMappingSet {
+        rules: vec![ToolQualityMappingRule {
+            source: "$.response.body.rates.EUR".to_owned(),
+            target: "$.output.rate".to_owned(),
+        }],
+    };
+
+    let report = analyze_tool_response_projection_quality(&mapping);
+
+    assert!(!report.blocking);
+    assert!(report.findings.is_empty());
+}
+
+#[test]
+fn marks_large_output_projection_as_info() {
+    let mapping = ToolQualityMappingSet {
+        rules: (0..12)
+            .map(|index| ToolQualityMappingRule {
+                source: format!("$.response.body.field_{index}"),
+                target: format!("$.output.field_{index}"),
+            })
+            .collect(),
+    };
+
+    let report = analyze_tool_response_projection_quality(&mapping);
+
+    assert!(has_finding(
+        &report,
+        "response_projection_many_fields",
+        ToolQualitySeverity::Info
+    ));
+}
+
 fn has_finding(report: &ToolQualityReport, code: &str, severity: ToolQualitySeverity) -> bool {
     report
         .findings