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agents.mcp-server.call-tool ​
Execute an MCP tool through a registered server
Execute a cached MCP tool through the workflow boundary.
Overview ​
| Property | Value |
|---|---|
| Workflow type | Linear |
| Library | App-agents |
| Version | 1.0 |
Triggers ​
| Source | Endpoint / Event | Description |
|---|---|---|
| API | POST /api/agents/mcp-servers/{mcp_server_uuid}/tools/{tool_name}/call | Execute an MCP tool from a registered server |
Input Schema ​
| Field | Type | Required | Default | Description |
|---|---|---|---|---|
organization_uuid | string | Yes | — | — |
mcp_server_uuid | string | Yes | — | — |
tool_name | string | Yes | — | — |
arguments | dict | No | — | — |
timeout_seconds | integer | No | — | — |
session_uuid | string | No | — | — |
tool_call_ref | string | No | — | — |
round_index | integer | No | — | — |
redact_result | boolean | No | — | — |
Output Schema ​
| Field | Type | Required | Default | Description |
|---|---|---|---|---|
mcp_server_uuid | string | No | — | — |
organization_uuid | string | No | — | — |
tool_name | string | No | — | — |
arguments | dict | No | — | — |
tool | json | No | — | — |
result | json | No | — | — |
raw_response | json | No | — | — |
is_error | boolean | No | — | — |
duration_ms | integer | No | — | — |
called_at | string | No | — | — |
session_uuid | string | No | — | — |
tool_call_ref | string | No | — | — |
round_index | integer | No | — | — |
redacted | boolean | No | — | — |
result_size_chars | integer | No | — | — |
elicitations | json | No | — | — |
elicitation_approval_uuid | string | No | — | — |
error_category | string | No | — | — |
error | string | No | — | — |
error_type | string | No | — | — |
failed_at | string | No | — | — |
failed_at_state | string | No | — | — |
failed_layer | json | No | — | — |
failed_step | string | No | — | — |
failure_reason | string | No | — | — |
States ​
| State | Initial | Terminal | Success | Auto-advance | Description |
|---|---|---|---|---|---|
initiated | Yes | No | — | run | — |
run | No | No | — | complete | — |
completed | No | Yes | Yes | — | — |
failed | No | Yes | No | — | — |
State Diagram ​
Transitions ​
| From | Action | To | Description |
|---|---|---|---|
initiated | run | run | — |
run | complete | completed | — |
* (any state) | fail | failed | — |
Outcomes ​
| Outcome | Type | Description | State Data Keys |
|---|---|---|---|
called | SUCCESS | MCP tool invoked | mcp_server_uuid, tool_name, result, is_error, organization_uuid |
failed | FAILURE | MCP tool invoked failed | failure_reason, error, error_type, failed_at_state, failed_step, failed_layer |
Business Errors ​
| Code | Message Template |
|---|---|
AGENTS_ORGANIZATION_CONTEXT_INVALID | Authenticated organization context is missing or does not match the workflow input |
AGENTS_MCP_SERVER_NOT_FOUND | MCP server {mcp_server_uuid} was not found in the organization |
AGENTS_MCP_AUTH_REJECTED | MCP server {mcp_server_uuid} rejected the stored credential |
AGENTS_MCP_AUTH_EXPIRED | The OAuth grant for MCP server {mcp_server_uuid} has expired and cannot be refreshed; the organization must re-authorize it |
AGENTS_VALIDATION_FAILED | Workflow input or domain state failed validation: |
AGENTS_CONFLICT | Conflicting agent domain state: |
AGENTS_PROVIDER_FAILED | Upstream provider or runner call failed: |
AGENTS_MCP_CALL_FAILED | MCP tool call failed for {tool_name}: |
API Usage ​
bash
POST /api/workflows/start
Content-Type: application/json
{
"workflow_type": "agents.mcp-server.call-tool",
"initial_data": {
"organization_uuid": "value",
"mcp_server_uuid": "value",
"tool_name": "value"
}
}