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Analyze Async

analyze-async

Read-onlyIdempotent

Detects async code issues by returning bundled AsyncFixer diagnostics and compiler diagnostic CS4014 for a selected solution, project, document, or project scope.

Instructions

Returns bundled AsyncFixer diagnostics and compiler diagnostic CS4014 for a selected scope.

Input Schema

TableJSON Schema

Name	Required	Description
`scope`	No	The optional search scope.
`workspace`	No	Provide workspaceId, alias, path, or any combination.
`findingsLimit`	No	Maximum number of results to return.

Output Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv1.0.4Oct 15, 2026

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "$defs": {
+    "warningInfo": {
+      "properties": {
+        "code": {
+          "description": "The stable machine-readable warning code.",
+          "type": "string"
+        },
+        "message": {
+          "description": "The human-readable warning message.",
+          "type": "string"
+        }
+      },
+      "required": [
+        "code",
+        "message"
+      ],
+      "type": "object"
+    }
+  },
+  "oneOf": [
+    {
+      "properties": {
+        "data": {
+          "description": "Tool-specific result payload.",
+          "properties": {
+            "findings": {
+              "description": "The returned findings.",
+              "properties": {
+                "hasMore": {
+                  "description": "Whether additional items were available beyond this page.",
+                  "type": "boolean"
+                },
+                "items": {
+                  "description": "Items returned in this page.",
+                  "items": {
+                    "properties": {
+                      "diagnostic": {
+                        "description": "The compiler diagnostic.",
+                        "properties": {
+                          "id": {
+                            "description": "The diagnostic identifier.",
+                            "type": "string"
+                          },
+                          "location": {
+                            "description": "The optional source location of the diagnostic.",
+                            "properties": {
+                              "column": {
+                                "description": "The one-based column number.",
+                                "type": "integer"
+                              },
+                              "document": {
+                                "description": "The resolved document.",
+                                "properties": {
+                                  "documentId": {
+                                    "description": "The document identifier.",
+                                    "type": "string"
+                                  },
+                                  "path": {
+                                    "description": "The normalized document path.",
+                                    "type": "string"
+                                  },
+                                  "projectId": {
+                                    "description": "The owning project identifier.",
+                                    "type": "string"
+                                  }
+                                },
+                                "required": [
+                                  "documentId",
+                                  "path",
+                                  "projectId"
+                                ],
+                                "type": [
+                                  "object",
+                                  "null"
+                                ]
+                              },
+                              "line": {
+                                "description": "The one-based line number.",
+                                "type": "integer"
+                              },
+                              "selector": {
+                                "description": "The canonical selector that can resolve this source location again.",
+                                "properties": {
+                                  "span": {
+                                    "properties": {
+                                      "document": {
+                                        "description": "Provide exactly one of path or documentId.",
+                                        "properties": {
+                                          "documentId": {
+                                            "description": "Workspace-local document ID.",
+                                            "type": [
+                                              "string",
+                                              "null"
+                                            ]
+                                          },
+                                          "path": {
+                                            "description": "Workspace-relative path.",
+                                            "type": [
+                                              "string",
+                                              "null"
+                                            ]
+                                          },
+                                          "project": {
+                                            "description": "Disambiguates documents with matching paths or IDs.",
+                                            "properties": {
+                                              "name": {
+                                                "type": [
+                                                  "string",
+                                                  "null"
+                                                ]
+                                              },
+                                              "path": {
+                                                "description": "Workspace-relative path.",
+                                                "type": [
+                                                  "string",
+                                                  "null"
+                                                ]
+                                              },
+                                              "projectId": {
+                                                "type": [
+                                                  "string",
+                                                  "null"
+                                                ]
+                                              },
+                                              "targetFramework": {
+                                                "type": [
+                                                  "string",
+                                                  "null"
+                                                ]
+                                              }
+                                            },
+                                            "type": [
+                                              "object",
+                                              "null"
+                                            ]
+                                          }
+                                        },
+                                        "type": "object"
+                                      },
+                                      "range": {
+                                        "description": "Zero-based UTF-16 range.",
+                                        "properties": {
+                                          "length": {
+                                            "description": "UTF-16 code-unit length.",
+                                            "maximum": 2147483647,
+                                            "minimum": 0,
+                                            "type": "integer"
+                                          },
+                                          "start": {
+                                            "description": "Zero-based UTF-16 offset.",
+                                            "maximum": 2147483647,
+                                            "minimum": 0,
+                                            "type": "integer"
+                                          }
+                                        },
+                                        "type": "object"
+                                      }
+                                    },
+                                    "required": [
+                                      "document",
+                                      "range"
+                                    ],
+                                    "type": "object"
+                                  }
+                                },
+                                "required": [
+                                  "span"
+                                ],
+                                "type": [
+                                  "object",
+                                  "null"
+                                ]
+                              },
+                              "snapshot": {
+                                "description": "The exact immutable workspace snapshot associated with this location.",
+                                "properties": {
+                                  "snapshotId": {
+                                    "format": "uuid",
+                                    "type": "string"
+                                  },
+                                  "transactionRevision": {
+                                    "type": [
+                                      "integer",
+                                      "null"
+                                    ]
+                                  },
+                                  "workspaceEpoch": {
+                                    "type": "integer"
+                                  },
+                                  "workspaceId": {
+                                    "format": "uuid",
+                                    "type": "string"
+                                  }
+                                },
+                                "required": [
+                                  "workspaceId",
+                                  "workspaceEpoch",
+                                  "snapshotId",
+                                  "transactionRevision"
+                                ],
+                                "type": "object"
+                              },
+                              "span": {
+                                "description": "The resolved text span.",
+                                "properties": {
+                                  "length": {
+                                    "description": "UTF-16 code-unit length.",
+                                    "maximum": 2147483647,
+                                    "minimum": 0,
+                                    "type": "integer"
+                                  },
+                                  "start": {
+                                    "description": "Zero-based UTF-16 offset.",
+                                    "maximum": 2147483647,
+                                    "minimum": 0,
+                                    "type": "integer"
+                                  }
+                                },
+                                "type": [
+                                  "object",
+                                  "null"
+                                ]
+                              }
+                            },
+                            "required": [
+                              "snapshot"
+                            ],
+                            "type": [
+                              "object",
+                              "null"
+                            ]
+                          },
+                          "message": {
+                            "description": "The diagnostic message.",
+                            "type": "string"
+                          },
+                          "severity": {
+                            "description": "The diagnostic severity.",
+                            "enum": [
+                              "Hidden",
+                              "Info",
+                              "Warning",
+                              "Error"
+                            ],
+                            "type": "string"
+                          }
+                        },
+                        "required": [
+                          "id",
+                          "message"
+                        ],
+                        "type": [
+                          "object",
+                          "null"
+                        ]
+                      }
+                    },
+                    "type": "object"
+                  },
+                  "type": [
+                    "array",
+                    "null"
+                  ]
+                },
+                "totalCount": {
+                  "description": "Complete result count, when available without additional expensive work.",
+                  "type": [
+                    "integer",
+                    "null"
+                  ]
+                }
+              },
+              "type": "object"
+            }
+          },
+          "type": [
+            "object",
+            "null"
+          ]
+        },
+        "ok": {
+          "const": true,
+          "description": "Whether the tool invocation succeeded."
+        },
+        "snapshot": {
+          "description": "Exact immutable workspace snapshot associated with the result, when available.",
+          "properties": {
+            "snapshotId": {
+              "format": "uuid",
+              "type": "string"
+            },
+            "transactionRevision": {
+              "type": [
+                "integer",
+                "null"
+              ]
+            },
+            "workspaceEpoch": {
+              "type": "integer"
+            },
+            "workspaceId": {
+              "format": "uuid",
+              "type": "string"
+            }
+          },
+          "required": [
+            "workspaceId",
+            "workspaceEpoch",
+            "snapshotId",
+            "transactionRevision"
+          ],
+          "type": "object"
+        },
+        "warnings": {
+          "description": "Non-fatal warnings the agent should consider.",
+          "items": {
+            "$ref": "#/$defs/warningInfo"
+          },
+          "type": "array"
+        }
+      },
+      "required": [
+        "ok",
+        "data",
+        "snapshot"
+      ],
+      "type": "object"
+    },
+    {
+      "properties": {
+        "continuation": {
+          "description": "Action the agent should take before retrying or continuing.",
+          "oneOf": [
+            {
+              "additionalProperties": false,
+              "properties": {
+                "instruction": {
+                  "description": "Agent-facing instruction explaining how to continue.",
+                  "minLength": 1,
+                  "type": "string"
+                },
+                "kind": {
+                  "const": "CallTool",
+                  "description": "Action required before the original request can continue."
+                },
+                "tool": {
+                  "description": "Tool to call before continuing the original request.",
+                  "minLength": 1,
+                  "type": "string"
+                }
+              },
+              "required": [
+                "kind",
+                "tool",
+                "instruction"
+              ],
+              "type": "object"
+            },
+            {
+              "additionalProperties": false,
+              "properties": {
+                "instruction": {
+                  "description": "Agent-facing instruction explaining how to continue.",
+                  "minLength": 1,
+                  "type": "string"
+                },
+                "kind": {
+                  "const": "ChooseTool",
+                  "description": "Action required before the original request can continue."
+                },
+                "tools": {
+                  "description": "Allowed tool choices from which the agent must select one.",
+                  "items": {
+                    "description": "Name of a tool the agent may choose.",
+                    "minLength": 1,
+                    "type": "string"
+                  },
+                  "minItems": 1,
+                  "type": "array",
+                  "uniqueItems": true
+                }
+              },
+              "required": [
+                "kind",
+                "tools",
+                "instruction"
+              ],
+              "type": "object"
+            },
+            {
+              "additionalProperties": false,
+              "properties": {
+                "instruction": {
+                  "description": "Agent-facing instruction explaining how to continue.",
+                  "minLength": 1,
+                  "type": "string"
+                },
+                "kind": {
+                  "const": "RetryRequest",
+                  "description": "Action required before the original request can continue."
+                }
+              },
+              "required": [
+                "kind",
+                "instruction"
+              ],
+              "type": "object"
+            },
+            {
+              "additionalProperties": false,
+              "properties": {
+                "instruction": {
+                  "description": "Agent-facing instruction explaining how to continue.",
+                  "minLength": 1,
+                  "type": "string"
+                },
+                "kind": {
+                  "const": "ReviseRequest",
+                  "description": "Action required before the original request can continue."
+                }
+              },
+              "required": [
+                "kind",
+                "instruction"
+              ],
+              "type": "object"
+            },
+            {
+              "additionalProperties": false,
+              "properties": {
+                "instruction": {
+                  "description": "Agent-facing instruction explaining how to continue.",
+                  "minLength": 1,
+                  "type": "string"
+                },
+                "kind": {
+                  "const": "ResolveExternally",
+                  "description": "Action required before the original request can continue."
+                }
+              },
+              "required": [
+                "kind",
+                "instruction"
+              ],
+              "type": "object"
+            }
+          ]
+        },
+        "diagnostics": {
+          "description": "Diagnostics that explain the failed invocation.",
+          "items": {
+            "properties": {
+              "id": {
+                "description": "The diagnostic identifier.",
+                "type": "string"
+              },
+              "location": {
+                "description": "The optional source location of the diagnostic.",
+                "properties": {
+                  "column": {
+                    "description": "The one-based column number.",
+                    "type": "integer"
+                  },
+                  "document": {
+                    "description": "The resolved document.",
+                    "properties": {
+                      "documentId": {
+                        "description": "The document identifier.",
+                        "type": "string"
+                      },
+                      "path": {
+                        "description": "The normalized document path.",
+                        "type": "string"
+                      },
+                      "projectId": {
+                        "description": "The owning project identifier.",
+                        "type": "string"
+                      }
+                    },
+                    "required": [
+                      "documentId",
+                      "path",
+                      "projectId"
+                    ],
+                    "type": [
+                      "object",
+                      "null"
+                    ]
+                  },
+                  "line": {
+                    "description": "The one-based line number.",
+                    "type": "integer"
+                  },
+                  "selector": {
+                    "description": "The canonical selector that can resolve this source location again.",
+                    "properties": {
+                      "span": {
+                        "properties": {
+                          "document": {
+                            "description": "Provide exactly one of path or documentId.",
+                            "properties": {
+                              "documentId": {
+                                "description": "Workspace-local document ID.",
+                                "type": [
+                                  "string",
+                                  "null"
+                                ]
+                              },
+                              "path": {
+                                "description": "Workspace-relative path.",
+                                "type": [
+                                  "string",
+                                  "null"
+                                ]
+                              },
+                              "project": {
+                                "description": "Disambiguates documents with matching paths or IDs.",
+                                "properties": {
+                                  "name": {
+                                    "type": [
+                                      "string",
+                                      "null"
+                                    ]
+                                  },
+                                  "path": {
+                                    "description": "Workspace-relative path.",
+                                    "type": [
+                                      "string",
+                                      "null"
+                                    ]
+                                  },
+                                  "projectId": {
+                                    "type": [
+                                      "string",
+                                      "null"
+                                    ]
+                                  },
+                                  "targetFramework": {
+                                    "type": [
+                                      "string",
+                                      "null"
+                                    ]
+                                  }
+                                },
+                                "type": [
+                                  "object",
+                                  "null"
+                                ]
+                              }
+                            },
+                            "type": "object"
+                          },
+                          "range": {
+                            "description": "Zero-based UTF-16 range.",
+                            "properties": {
+                              "length": {
+                                "description": "UTF-16 code-unit length.",
+                                "maximum": 2147483647,
+                                "minimum": 0,
+                                "type": "integer"
+                              },
+                              "start": {
+                                "description": "Zero-based UTF-16 offset.",
+                                "maximum": 2147483647,
+                                "minimum": 0,
+                                "type": "integer"
+                              }
+                            },
+                            "type": "object"
+                          }
+                        },
+                        "required": [
+                          "document",
+                          "range"
+                        ],
+                        "type": "object"
+                      }
+                    },
+                    "required": [
+                      "span"
+                    ],
+                    "type": [
+                      "object",
+                      "null"
+                    ]
+                  },
+                  "snapshot": {
+                    "description": "The exact immutable workspace snapshot associated with this location.",
+                    "properties": {
+                      "snapshotId": {
+                        "format": "uuid",
+                        "type": "string"
+                      },
+                      "transactionRevision": {
+                        "type": [
+                          "integer",
+                          "null"
+                        ]
+                      },
+                      "workspaceEpoch": {
+                        "type": "integer"
+                      },
+                      "workspaceId": {
+                        "format": "uuid",
+                        "type": "string"
+                      }
+                    },
+                    "required": [
+                      "workspaceId",
+                      "workspaceEpoch",
+                      "snapshotId",
+                      "transactionRevision"
+                    ],
+                    "type": "object"
+                  },
+                  "span": {
+                    "description": "The resolved text span.",
+                    "properties": {
+                      "length": {
+                        "description": "UTF-16 code-unit length.",
+                        "maximum": 2147483647,
+                        "minimum": 0,
+                        "type": "integer"
+                      },
+                      "start": {
+                        "description": "Zero-based UTF-16 offset.",
+                        "maximum": 2147483647,
+                        "minimum": 0,
+                        "type": "integer"
+                      }
+                    },
+                    "type": [
+                      "object",
+                      "null"
+                    ]
+                  }
+                },
+                "required": [
+                  "snapshot"
+                ],
+                "type": [
+                  "object",
+                  "null"
+                ]
+              },
+              "message": {
+                "description": "The diagnostic message.",
+                "type": "string"
+              },
+              "severity": {
+                "description": "The diagnostic severity.",
+                "enum": [
+                  "Hidden",
+                  "Info",
+                  "Warning",
+                  "Error"
+                ],
+                "type": "string"
+              }
+            },
+            "required": [
+              "id",
+              "message"
+            ],
+            "type": "object"
+          },
+          "type": "array"
+        },
+        "error": {
+          "description": "Structured error details when the invocation failed.",
+          "properties": {
+            "code": {
+              "description": "Stable machine-readable error code.",
+              "type": "string"
+            },
+            "correlationId": {
+              "description": "Correlation identifier for matching the failure to server-side diagnostics, when available.",
+              "type": [
+                "string",
+                "null"
+              ]
+            },
+            "message": {
+              "description": "Human-readable explanation of the failure.",
+              "type": "string"
+            }
+          },
+          "required": [
+            "code",
+            "message"
+          ],
+          "type": "object"
+        },
+        "ok": {
+          "const": false,
+          "description": "Whether the tool invocation succeeded."
+        },
+        "warnings": {
+          "description": "Non-fatal warnings the agent should consider.",
+          "items": {
+            "$ref": "#/$defs/warningInfo"
+          },
+          "type": "array"
+        }
+      },
+      "required": [
+        "ok",
+        "error"
+      ],
+      "type": "object"
+    },
+    {
+      "properties": {
+        "diagnostics": {
+          "description": "Diagnostics that explain the failed invocation.",
+          "properties": {
+            "detailsAvailable": {
+              "const": true
+            },
+            "detailsTool": {
+              "const": "get-error-details"
+            }
+          },
+          "required": [
+            "detailsAvailable",
+            "detailsTool"
+          ],
+          "type": "object"
+        },
+        "error": {
+          "description": "Structured error details when the invocation failed.",
+          "properties": {
+            "code": {
+              "const": "UnhandledException"
+            },
+            "correlationId": {
+              "format": "uuid",
+              "type": "string"
+            },
+            "message": {
+              "const": "Tool execution failed."
+            }
+          },
+          "required": [
+            "code",
+            "message",
+            "correlationId"
+          ],
+          "type": "object"
+        },
+        "ok": {
+          "const": false,
+          "description": "Whether the tool invocation succeeded."
+        },
+        "reporting": {
+          "description": "Error-reporting workflow available for an unhandled failure.",
+          "properties": {
+            "canPrepare": {
+              "type": "boolean"
+            },
+            "prepareTool": {
+              "type": [
+                "string",
+                "null"
+              ]
+            },
+            "state": {
+              "enum": [
+                "Available",
+                "AlwaysApproved",
+                "DisabledByConfiguration",
+                "ApprovalUnavailable"
+              ],
+              "type": "string"
+            }
+          },
+          "required": [
+            "state"
+          ],
+          "type": "object"
+        }
+      },
+      "required": [
+        "ok",
+        "error",
+        "diagnostics"
+      ],
+      "type": "object"
+    }
+  ],
+  "type": "object"
+}

First observedv1.0.2Oct 15, 2026

TDQS

A3.6/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The annotations already declare readOnlyHint, idempotentHint, openWorldHint=false, and destructiveHint=false, so safety is covered without description help. The description adds the specific diagnostic bundle being returned, but does not explain scope defaults, whether analysis is fresh or cached, or how findingsLimit truncation behaves.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

It is a single front-loaded sentence with zero filler or repetition. Every word earns its place by identifying the return content and the scoping condition.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need no description, and the annotations plus full schema coverage handle safety and parameter semantics. The description adequately states what the tool returns, though it omits sibling routing guidance that would make selection among the large analyze-* family fully self-contained.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so scope, workspace, and findingsLimit are already fully documented in the schema, including the default of 50 for findingsLimit. The description adds only 'for a selected scope' and no further format, default, or interaction details, which meets the baseline 3 for high schema coverage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('Returns') and names the exact diagnostic sets produced: bundled AsyncFixer diagnostics and compiler diagnostic CS4014. This distinguishes it from broader siblings such as get-diagnostics and from other analyzers like analyze-nullability or analyze-disposables.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It never says when to choose this tool over get-diagnostics or the other analyze-* siblings, nor does it give any prerequisites or exclusions. The only usage signal is implicit in the tool name and the specific diagnostic names.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

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