Add approval mode selection

crates/crank-community-mcp/src/app.rs

@@ -15,7 +15,7 @@ use axum::{
 use crank_core::{
     ApprovalRequest, ApprovalRequestId, ApprovalRequestStatus, AuthProfile, CoordinationStateStore,
     InvocationLevel, InvocationLog, InvocationLogId, InvocationSource, InvocationStatus,
-    PlatformApiKeyScope, SecretId,
+    OperationApprovalMode, PlatformApiKeyScope, SecretId,
 };
 use crank_registry::{
     ApprovalRequestRecord, CreateApprovalRequest, CreateInvocationLogRequest,
@@ -79,6 +79,8 @@ pub(super) struct AppState {
 struct InitializeParams {
     #[serde(rename = "protocolVersion")]
     protocol_version: String,
+    #[serde(default)]
+    capabilities: Value,
 }
 
 #[derive(Debug, Serialize, Deserialize)]
@@ -955,7 +957,7 @@ async fn handle_base_tool_call(
     let tool = execution.tool;
     let arguments = execution.arguments;
     let operation = runtime_operation(&tool);
-    if let Some(response) = maybe_create_pending_approval(
+    if let Some(response) = maybe_handle_approval_policy(
         &state,
         session,
         message,
@@ -1052,7 +1054,7 @@ async fn handle_base_tool_call(
     }
 }
 
-async fn maybe_create_pending_approval(
+async fn maybe_handle_approval_policy(
     state: &Arc<AppState>,
     session: &SessionState,
     message: &Value,
@@ -1066,6 +1068,42 @@ async fn maybe_create_pending_approval(
         return None;
     }
 
+    match policy.mode {
+        OperationApprovalMode::Custom => {
+            maybe_create_custom_pending_approval(
+                state,
+                session,
+                message,
+                response_mode,
+                tool,
+                arguments,
+                transport_request_id,
+            )
+            .await
+        }
+        OperationApprovalMode::Elicitation => Some(handle_elicitation_approval(
+            session,
+            message,
+            response_mode,
+            tool,
+            arguments,
+            policy.elicitation_message.as_deref(),
+            transport_request_id,
+        )),
+    }
+}
+
+async fn maybe_create_custom_pending_approval(
+    state: &Arc<AppState>,
+    session: &SessionState,
+    message: &Value,
+    response_mode: ResponseMode,
+    tool: &PublishedAgentTool,
+    arguments: &Value,
+    transport_request_id: &str,
+) -> Option<Response> {
+    let policy = tool.operation.execution_config.approval_policy.as_ref()?;
+
     let approval_id = ApprovalRequestId::new(format!("approval_{}", uuid::Uuid::now_v7().simple()));
     let now = OffsetDateTime::now_utc();
     let expires_at = now + time::Duration::seconds(i64::from(policy.ttl_seconds));
@@ -1145,6 +1183,54 @@ async fn maybe_create_pending_approval(
     ))
 }
 
+fn handle_elicitation_approval(
+    session: &SessionState,
+    message: &Value,
+    response_mode: ResponseMode,
+    tool: &PublishedAgentTool,
+    arguments: &Value,
+    elicitation_message: Option<&str>,
+    transport_request_id: &str,
+) -> Response {
+    if !session.supports_elicitation {
+        return tool_error_response(
+            message,
+            response_mode,
+            &session.protocol_version,
+            generic_tool_error_contract(
+                "approval_elicitation_not_supported",
+                "operation requires MCP Elicitation, but the MCP client did not advertise elicitation capability",
+                transport_request_id,
+                false,
+                Some(
+                    "Выберите Custom MCP Approval или подключите MCP-клиент с поддержкой elicitation.",
+                ),
+            ),
+        );
+    }
+
+    let payload_preview = tool
+        .operation
+        .execution_config
+        .approval_policy
+        .as_ref()
+        .and_then(|policy| policy.show_payload_preview.then(|| arguments.clone()))
+        .unwrap_or(Value::Null);
+
+    success_tool_response(
+        message,
+        response_mode,
+        &session.protocol_version,
+        json!({
+            "status": "elicitation_required",
+            "message": elicitation_message.unwrap_or("Confirm operation execution."),
+            "tool": tool.tool_name,
+            "payload_preview": payload_preview,
+            "note": "This MCP client advertised elicitation support. Full elicitation/create continuation is handled by compatible client integrations.",
+        }),
+    )
+}
+
 fn approval_url_for(tool: &PublishedAgentTool, approval_id: &ApprovalRequestId) -> String {
     format!(
         "/v1/{}/{}/approvals/{}",
@@ -1191,12 +1277,17 @@ async fn handle_initialize(
     };
     let now = OffsetDateTime::now_utc();
     let expires_at = add_millis(now, TRANSPORT_SESSION_TTL_MS);
+    let supports_elicitation = initialize_params
+        .capabilities
+        .get("elicitation")
+        .is_some_and(Value::is_object);
     let session_id = match state
         .sessions
         .create(
             protocol_version,
             &path.workspace_slug,
             &path.agent_slug,
+            supports_elicitation,
             now,
             Some(expires_at),
         )

crates/crank-community-mcp/src/session.rs

@@ -3,7 +3,7 @@ use std::{collections::HashMap, sync::Arc};
 use async_trait::async_trait;
 use crank_registry::PostgresPoolConfig;
 use sqlx::{
-    PgPool,
+    PgPool, Row,
     postgres::{PgConnectOptions, PgPoolOptions},
     query,
 };
@@ -17,6 +17,7 @@ pub struct SessionState {
     pub id: String,
     pub protocol_version: String,
     pub initialized: bool,
+    pub supports_elicitation: bool,
     pub workspace_slug: String,
     pub agent_slug: String,
     pub created_at: OffsetDateTime,
@@ -37,6 +38,7 @@ pub trait TransportSessionStore: Send + Sync {
         protocol_version: &str,
         workspace_slug: &str,
         agent_slug: &str,
+        supports_elicitation: bool,
         now: OffsetDateTime,
         expires_at: Option<OffsetDateTime>,
     ) -> Result<String, SessionStoreError>;
@@ -100,6 +102,7 @@ impl TransportSessionStore for InMemorySessionStore {
         protocol_version: &str,
         workspace_slug: &str,
         agent_slug: &str,
+        supports_elicitation: bool,
         now: OffsetDateTime,
         expires_at: Option<OffsetDateTime>,
     ) -> Result<String, SessionStoreError> {
@@ -112,6 +115,7 @@ impl TransportSessionStore for InMemorySessionStore {
                 id: session_id.clone(),
                 protocol_version: protocol_version.to_owned(),
                 initialized: false,
+                supports_elicitation,
                 workspace_slug: workspace_slug.to_owned(),
                 agent_slug: agent_slug.to_owned(),
                 created_at: now,
@@ -169,6 +173,7 @@ impl TransportSessionStore for PostgresTransportSessionStore {
         protocol_version: &str,
         workspace_slug: &str,
         agent_slug: &str,
+        supports_elicitation: bool,
         now: OffsetDateTime,
         expires_at: Option<OffsetDateTime>,
     ) -> Result<String, SessionStoreError> {
@@ -178,17 +183,19 @@ impl TransportSessionStore for PostgresTransportSessionStore {
                 id,
                 protocol_version,
                 initialized,
+                supports_elicitation,
                 workspace_slug,
                 agent_slug,
                 created_at,
                 updated_at,
                 expires_at
              ) values (
-                $1, $2, false, $3, $4, $5::timestamptz, $5::timestamptz, $6::timestamptz
+                $1, $2, false, $3, $4, $5, $6::timestamptz, $6::timestamptz, $7::timestamptz
              )",
         )
         .bind(&session_id)
         .bind(protocol_version)
+        .bind(supports_elicitation)
         .bind(workspace_slug)
         .bind(agent_slug)
         .bind(now)
@@ -203,20 +210,21 @@ impl TransportSessionStore for PostgresTransportSessionStore {
     }
 
     async fn get(&self, session_id: &str) -> Result<Option<SessionState>, SessionStoreError> {
-        let row = sqlx::query!(
+        let row = sqlx::query(
             "select
                 id,
                 protocol_version,
                 initialized,
+                supports_elicitation,
                 workspace_slug,
                 agent_slug,
-                created_at as \"created_at!: OffsetDateTime\",
-                updated_at as \"updated_at!: OffsetDateTime\",
-                expires_at as \"expires_at: OffsetDateTime\"
+                created_at,
+                updated_at,
+                expires_at
              from mcp_transport_sessions
              where id = $1",
-            session_id,
         )
+        .bind(session_id)
         .fetch_optional(&self.pool)
         .await
         .map_err(|error| SessionStoreError {
@@ -224,14 +232,15 @@ impl TransportSessionStore for PostgresTransportSessionStore {
         })?;
 
         let Some(session) = row.map(|row| SessionState {
-            id: row.id,
-            protocol_version: row.protocol_version,
-            initialized: row.initialized,
-            workspace_slug: row.workspace_slug,
-            agent_slug: row.agent_slug,
-            created_at: row.created_at,
-            updated_at: row.updated_at,
-            expires_at: row.expires_at,
+            id: row.get("id"),
+            protocol_version: row.get("protocol_version"),
+            initialized: row.get("initialized"),
+            supports_elicitation: row.get("supports_elicitation"),
+            workspace_slug: row.get("workspace_slug"),
+            agent_slug: row.get("agent_slug"),
+            created_at: row.get("created_at"),
+            updated_at: row.get("updated_at"),
+            expires_at: row.get("expires_at"),
         }) else {
             return Ok(None);
         };
@@ -291,6 +300,7 @@ async fn apply_postgres_migrations(pool: &PgPool) -> Result<(), SessionStoreErro
             id text primary key,
             protocol_version text not null,
             initialized boolean not null default false,
+            supports_elicitation boolean not null default false,
             workspace_slug text not null,
             agent_slug text not null,
             created_at timestamptz not null,
@@ -304,6 +314,13 @@ async fn apply_postgres_migrations(pool: &PgPool) -> Result<(), SessionStoreErro
         details: error.to_string(),
     })?;
 
+    query("alter table mcp_transport_sessions add column if not exists supports_elicitation boolean not null default false")
+        .execute(pool)
+        .await
+        .map_err(|error| SessionStoreError {
+            details: error.to_string(),
+        })?;
+
     query(
         "alter table mcp_transport_sessions add column if not exists expires_at timestamptz null",
     )

crates/crank-community-mcp/tests/integration/session.rs

@@ -32,6 +32,7 @@ async fn postgres_transport_sessions_survive_store_reconnect() {
             "2025-11-25",
             "default",
             "sales",
+            false,
             created_at,
             Some(created_at + time::Duration::days(30)),
         )
@@ -73,6 +74,7 @@ async fn postgres_transport_sessions_evict_expired_rows_on_read() {
             "2025-11-25",
             "default",
             "sales",
+            false,
             timestamp("2026-05-01T10:00:00Z"),
             Some(timestamp("2026-05-01T10:00:01Z")),
         )

crates/crank-community-mcp/tests/unit/session.rs

@@ -13,7 +13,7 @@ async fn creates_and_reads_transport_sessions() {
     let created_at = timestamp("2026-05-01T10:00:00Z");
 
     let session_id = store
-        .create("2025-11-25", "default", "sales", created_at, None)
+        .create("2025-11-25", "default", "sales", false, created_at, None)
         .await
         .unwrap();
     let session = store.get(&session_id).await.unwrap().unwrap();
@@ -23,6 +23,7 @@ async fn creates_and_reads_transport_sessions() {
     assert_eq!(session.workspace_slug, "default");
     assert_eq!(session.agent_slug, "sales");
     assert!(!session.initialized);
+    assert!(!session.supports_elicitation);
     assert_eq!(session.created_at, created_at);
     assert_eq!(session.updated_at, created_at);
 }
@@ -34,7 +35,7 @@ async fn marks_transport_sessions_initialized() {
     let initialized_at = timestamp("2026-05-01T10:00:05Z");
 
     let session_id = store
-        .create("2025-11-25", "default", "sales", created_at, None)
+        .create("2025-11-25", "default", "sales", false, created_at, None)
         .await
         .unwrap();
 
@@ -61,6 +62,7 @@ async fn drops_expired_in_memory_transport_sessions_on_read() {
             "2025-11-25",
             "default",
             "sales",
+            false,
             created_at,
             Some(expires_at),
         )

crates/crank-core/src/lib.rs

@@ -43,10 +43,10 @@ pub mod domain {
     };
     pub use crate::operation::{
         ConfigExport, ConfirmationPolicy, ExecutionConfig, GeneratedDraft, GeneratedDraftStatus,
-        IdempotencyMode, IdempotencyPolicy, Operation, OperationApprovalPayloadPreviewMode,
-        OperationApprovalPolicy, OperationApprovalRiskLevel, OperationSafetyClass,
-        OperationSafetyPolicy, OperationStatus, ResponseCachePolicy, RestTarget, RetryPolicy,
-        Samples, Target, ToolDescription, ToolExample, WizardState,
+        IdempotencyMode, IdempotencyPolicy, Operation, OperationApprovalMode,
+        OperationApprovalPayloadPreviewMode, OperationApprovalPolicy, OperationApprovalRiskLevel,
+        OperationSafetyClass, OperationSafetyPolicy, OperationStatus, ResponseCachePolicy,
+        RestTarget, RetryPolicy, Samples, Target, ToolDescription, ToolExample, WizardState,
     };
     pub use crate::protocol::{AuthKind, ExportMode, HttpMethod, Protocol};
     pub use crate::secret::{Secret, SecretKind, SecretStatus, SecretVersion};
@@ -133,10 +133,10 @@ pub use observability::{
 };
 pub use operation::{
     ConfigExport, ConfirmationPolicy, ExecutionConfig, GeneratedDraft, GeneratedDraftStatus,
-    IdempotencyMode, IdempotencyPolicy, Operation, OperationApprovalPayloadPreviewMode,
-    OperationApprovalPolicy, OperationApprovalRiskLevel, OperationSafetyClass,
-    OperationSafetyPolicy, OperationStatus, ResponseCachePolicy, RestTarget, RetryPolicy, Samples,
-    Target, ToolDescription, ToolExample, WizardState,
+    IdempotencyMode, IdempotencyPolicy, Operation, OperationApprovalMode,
+    OperationApprovalPayloadPreviewMode, OperationApprovalPolicy, OperationApprovalRiskLevel,
+    OperationSafetyClass, OperationSafetyPolicy, OperationStatus, ResponseCachePolicy, RestTarget,
+    RetryPolicy, Samples, Target, ToolDescription, ToolExample, WizardState,
 };
 pub use protocol::{AuthKind, ExportMode, HttpMethod, Protocol};
 pub use secret::{Secret, SecretKind, SecretStatus, SecretVersion};

crates/crank-core/src/operation.rs

@@ -121,13 +121,25 @@ pub enum OperationApprovalPayloadPreviewMode {
     MaskedJson,
 }
 
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum OperationApprovalMode {
+    #[default]
+    Custom,
+    Elicitation,
+}
+
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 pub struct OperationApprovalPolicy {
     pub required: bool,
+    #[serde(default)]
+    pub mode: OperationApprovalMode,
     pub risk_level: OperationApprovalRiskLevel,
     pub ttl_seconds: u32,
     pub show_payload_preview: bool,
     pub payload_preview_mode: OperationApprovalPayloadPreviewMode,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub elicitation_message: Option<String>,
 }
 
 #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize)]