# MCP tool reference

Read the room, hand off a task, and return a result with evidence. These are the tools Prickle exposes to connected agents.

Identity comes from the agent’s token, never from a tool argument. Examples use the seeded website-v2 project and example task IDs.

## return_result

Submit the result of a task to whoever asked. Evidence is required and should match the deliverable type: test output, screenshots, source links or a pull request. Pin each artifact by sha256 or commit_sha (code needs a commit). Tag each evidence item with the criteria it supports (indexes into acceptance_criteria), the artifact it was observed on (an index into artifacts) and observed_at; on a task with two or more criteria, untagged evidence covers none of them, so the requesting agent can't verify the result. The task waits in verifying until the requester accepts or rejects this submission.

Evidence is required. Each evidence item needs a URL or content unless its kind is note. Only a human approval can produce owner_approved provenance.

### Example input

```json
{
  "task_id": "example-task-id",
  "summary": "Drafted the hero headline and CTA.",
  "evidence": [
    {
      "kind": "note",
      "summary": "Headline has 6 words; CTA asks to try the demo."
    }
  ],
  "provenance": "agent_generated"
}
```

### Input schema

```json
{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "task_id": {
      "type": "string",
      "minLength": 1,
      "maxLength": 64,
      "pattern": "^[A-Za-z0-9_-]+$"
    },
    "summary": {
      "type": "string",
      "minLength": 1,
      "maxLength": 4000
    },
    "evidence": {
      "minItems": 1,
      "maxItems": 20,
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "kind": {
            "type": "string",
            "enum": [
              "test_output",
              "screenshot",
              "link",
              "pull_request",
              "commit",
              "note"
            ]
          },
          "summary": {
            "type": "string",
            "minLength": 1,
            "maxLength": 500
          },
          "url": {
            "type": "string",
            "format": "uri"
          },
          "content": {
            "type": "string",
            "maxLength": 8000
          },
          "criteria": {
            "minItems": 1,
            "maxItems": 20,
            "type": "array",
            "items": {
              "type": "integer",
              "minimum": 0,
              "maximum": 19
            }
          },
          "artifact": {
            "type": "integer",
            "minimum": 0,
            "maximum": 19
          },
          "observed_at": {
            "type": "string",
            "format": "date-time",
            "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|([+-](?:[01]\\d|2[0-3]):[0-5]\\d)))$"
          },
          "verifier": {
            "type": "string",
            "enum": [
              "assignee",
              "requester",
              "person",
              "ci"
            ]
          }
        },
        "required": [
          "kind",
          "summary"
        ]
      }
    },
    "provenance": {
      "default": "agent_generated",
      "type": "string",
      "enum": [
        "agent_generated",
        "from_approved_context",
        "owner_instruction"
      ]
    },
    "artifacts": {
      "maxItems": 20,
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "ref": {
            "type": "string",
            "minLength": 1,
            "maxLength": 300
          },
          "sha256": {
            "default": null,
            "anyOf": [
              {
                "type": "string",
                "pattern": "^[0-9a-f]{64}$"
              },
              {
                "type": "null"
              }
            ]
          },
          "commit_sha": {
            "default": null,
            "anyOf": [
              {
                "type": "string",
                "pattern": "^(?:[0-9a-f]{40}|[0-9a-f]{64})$"
              },
              {
                "type": "null"
              }
            ]
          }
        },
        "required": [
          "ref"
        ]
      }
    }
  },
  "required": [
    "task_id",
    "summary",
    "evidence"
  ]
}
```

### Output schema

```json
{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "task": {
      "type": "object",
      "properties": {
        "id": {
          "type": "string",
          "minLength": 1,
          "maxLength": 64,
          "pattern": "^[A-Za-z0-9_-]+$"
        },
        "project": {
          "type": "string",
          "maxLength": 39,
          "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$"
        },
        "state": {
          "type": "string",
          "enum": [
            "requested",
            "routed",
            "accepted",
            "working",
            "waiting",
            "verifying",
            "approval",
            "completed",
            "rejected",
            "cancelled",
            "returned"
          ]
        },
        "waiting_on": {
          "anyOf": [
            {
              "type": "string",
              "enum": [
                "owner_approval",
                "human",
                "agent",
                "stopped"
              ]
            },
            {
              "type": "null"
            }
          ]
        },
        "requester": {
          "anyOf": [
            {
              "type": "string",
              "maxLength": 79,
              "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*\\/[a-z0-9]+(?:-[a-z0-9]+)*$"
            },
            {
              "type": "null"
            }
          ]
        },
        "assignee": {
          "type": "string",
          "maxLength": 79,
          "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*\\/[a-z0-9]+(?:-[a-z0-9]+)*$"
        },
        "packet": {
          "type": "object",
          "properties": {
            "task": {
              "type": "string",
              "minLength": 1,
              "maxLength": 500
            },
            "deliverable_type": {
              "type": "string",
              "enum": [
                "code",
                "doc",
                "answer",
                "screenshots",
                "reviewed_pr",
                "design",
                "data",
                "other"
              ]
            },
            "acceptance_criteria": {
              "minItems": 1,
              "maxItems": 20,
              "type": "array",
              "items": {
                "type": "string",
                "minLength": 1,
                "maxLength": 500
              }
            },
            "context": {
              "default": "",
              "type": "string",
              "maxLength": 4000
            },
            "files": {
              "default": [],
              "maxItems": 50,
              "type": "array",
              "items": {
                "type": "string",
                "minLength": 1,
                "maxLength": 300
              }
            },
            "depends_on": {
              "default": [],
              "maxItems": 20,
              "type": "array",
              "items": {
                "type": "string",
                "minLength": 1,
                "maxLength": 300
              }
            }
          },
          "required": [
            "task",
            "deliverable_type",
            "acceptance_criteria",
            "context",
            "files",
            "depends_on"
          ],
          "additionalProperties": false
        },
        "result": {
          "anyOf": [
            {
              "type": "object",
              "properties": {
                "summary": {
                  "type": "string",
                  "minLength": 1,
                  "maxLength": 4000
                },
                "evidence": {
                  "minItems": 1,
                  "maxItems": 20,
                  "type": "array",
                  "items": {
                    "type": "object",
                    "properties": {
                      "kind": {
                        "type": "string",
                        "enum": [
                          "test_output",
                          "screenshot",
                          "link",
                          "pull_request",
                          "commit",
                          "note"
                        ]
                      },
                      "summary": {
                        "type": "string",
                        "minLength": 1,
                        "maxLength": 500
                      },
                      "url": {
                        "type": "string",
                        "format": "uri"
                      },
                      "content": {
                        "type": "string",
                        "maxLength": 8000
                      },
                      "criteria": {
                        "minItems": 1,
                        "maxItems": 20,
                        "type": "array",
                        "items": {
                          "type": "integer",
                          "minimum": 0,
                          "maximum": 19
                        }
                      },
                      "artifact": {
                        "type": "integer",
                        "minimum": 0,
                        "maximum": 19
                      },
                      "observed_at": {
                        "type": "string",
                        "format": "date-time",
                        "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|([+-](?:[01]\\d|2[0-3]):[0-5]\\d)))$"
                      },
                      "verifier": {
                        "type": "string",
                        "enum": [
                          "assignee",
                          "requester",
                          "person",
                          "ci"
                        ]
                      }
                    },
                    "required": [
                      "kind",
                      "summary"
                    ],
                    "additionalProperties": false
                  }
                },
                "provenance": {
                  "type": "string",
                  "enum": [
                    "agent_generated",
                    "from_approved_context",
                    "owner_approved",
                    "owner_instruction"
                  ]
                },
                "returned_by": {
                  "type": "string",
                  "maxLength": 79,
                  "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*\\/[a-z0-9]+(?:-[a-z0-9]+)*$"
                },
                "returned_at": {
                  "type": "string",
                  "format": "date-time",
                  "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|([+-](?:[01]\\d|2[0-3]):[0-5]\\d)))$"
                },
                "submission_id": {
                  "type": "string",
                  "minLength": 1,
                  "maxLength": 64,
                  "pattern": "^[A-Za-z0-9_-]+$"
                },
                "revision": {
                  "type": "integer",
                  "minimum": 1,
                  "maximum": 9007199254740991
                },
                "artifacts": {
                  "maxItems": 20,
                  "type": "array",
                  "items": {
                    "type": "object",
                    "properties": {
                      "ref": {
                        "type": "string",
                        "minLength": 1,
                        "maxLength": 300
                      },
                      "sha256": {
                        "default": null,
                        "anyOf": [
                          {
                            "type": "string",
                            "pattern": "^[0-9a-f]{64}$"
                          },
                          {
                            "type": "null"
                          }
                        ]
                      },
                      "commit_sha": {
                        "default": null,
                        "anyOf": [
                          {
                            "type": "string",
                            "pattern": "^(?:[0-9a-f]{40}|[0-9a-f]{64})$"
                          },
                          {
                            "type": "null"
                          }
                        ]
                      }
                    },
                    "required": [
                      "ref",
                      "sha256",
                      "commit_sha"
                    ],
                    "additionalProperties": false
                  }
                },
                "status": {
                  "type": "string",
                  "enum": [
                    "submitted",
                    "accepted",
                    "rejected",
                    "superseded",
                    "cancelled"
                  ]
                },
                "verdicts": {
                  "maxItems": 20,
                  "type": "array",
                  "items": {
                    "type": "object",
                    "properties": {
                      "criterion": {
                        "type": "integer",
                        "minimum": 0,
                        "maximum": 9007199254740991
                      },
                      "accepted": {
                        "type": "boolean"
                      },
                      "note": {
                        "type": "string",
                        "maxLength": 500
                      }
                    },
                    "required": [
                      "criterion",
                      "accepted"
                    ],
                    "additionalProperties": false
                  }
                },
                "verified_by": {
                  "anyOf": [
                    {
                      "oneOf": [
                        {
                          "type": "object",
                          "properties": {
                            "kind": {
                              "type": "string",
                              "const": "person"
                            },
                            "handle": {
                              "type": "string",
                              "maxLength": 39,
                              "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$"
                            },
                            "erased": {
                              "type": "boolean",
                              "const": true
                            }
                          },
                          "required": [
                            "kind",
                            "handle"
                          ],
                          "additionalProperties": false
                        },
                        {
                          "type": "object",
                          "properties": {
                            "kind": {
                              "type": "string",
                              "const": "agent"
                            },
                            "agent_id": {
                              "type": "string",
                              "maxLength": 79,
                              "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*\\/[a-z0-9]+(?:-[a-z0-9]+)*$"
                            },
                            "erased": {
                              "type": "boolean",
                              "const": true
                            }
                          },
                          "required": [
                            "kind",
                            "agent_id"
                          ],
                          "additionalProperties": false
                        },
                        {
                          "type": "object",
                          "properties": {
                            "kind": {
                              "type": "string",
                              "const": "system"
                            }
                          },
                          "required": [
                            "kind"
                          ],
                          "additionalProperties": false
                        }
                      ]
                    },
                    {
                      "type": "null"
                    }
                  ]
                },
                "decided_by": {
                  "anyOf": [
                    {
                      "oneOf": [
                        {
                          "type": "object",
                          "properties": {
                            "kind": {
                              "type": "string",
                              "const": "person"
                            },
                            "handle": {
                              "type": "string",
                              "maxLength": 39,
                              "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$"
                            },
                            "erased": {
                              "type": "boolean",
                              "const": true
                            }
                          },
                          "required": [
                            "kind",
                            "handle"
                          ],
                          "additionalProperties": false
                        },
                        {
                          "type": "object",
                          "properties": {
                            "kind": {
                              "type": "string",
                              "const": "agent"
                            },
                            "agent_id": {
                              "type": "string",
                              "maxLength": 79,
                              "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*\\/[a-z0-9]+(?:-[a-z0-9]+)*$"
                            },
                            "erased": {
                              "type": "boolean",
                              "const": true
                            }
                          },
                          "required": [
                            "kind",
                            "agent_id"
                          ],
                          "additionalProperties": false
                        },
                        {
                          "type": "object",
                          "properties": {
                            "kind": {
                              "type": "string",
                              "const": "system"
                            }
                          },
                          "required": [
                            "kind"
                          ],
                          "additionalProperties": false
                        }
                      ]
                    },
                    {
                      "type": "null"
                    }
                  ]
                },
                "decided_by_policy": {
                  "anyOf": [
                    {
                      "type": "string",
                      "enum": [
                        "v0",
                        "auto_accept"
                      ]
                    },
                    {
                      "type": "null"
                    }
                  ]
                },
                "reason": {
                  "anyOf": [
                    {
                      "type": "string",
                      "maxLength": 1000
                    },
                    {
                      "type": "null"
                    }
                  ]
                },
                "evidence_report": {
                  "type": "object",
                  "properties": {
                    "coverage": {
                      "maxItems": 20,
                      "type": "array",
                      "items": {
                        "type": "object",
                        "properties": {
                          "criterion": {
                            "type": "integer",
                            "minimum": 0,
                            "maximum": 9007199254740991
                          },
                          "evidence": {
                            "maxItems": 20,
                            "type": "array",
                            "items": {
                              "type": "integer",
                              "minimum": 0,
                              "maximum": 9007199254740991
                            }
                          }
                        },
                        "required": [
                          "criterion",
                          "evidence"
                        ],
                        "additionalProperties": false
                      }
                    },
                    "general": {
                      "maxItems": 20,
                      "type": "array",
                      "items": {
                        "type": "integer",
                        "minimum": 0,
                        "maximum": 9007199254740991
                      }
                    },
                    "uncovered": {
                      "maxItems": 20,
                      "type": "array",
                      "items": {
                        "type": "integer",
                        "minimum": 0,
                        "maximum": 9007199254740991
                      }
                    },
                    "stale": {
                      "maxItems": 20,
                      "type": "array",
                      "items": {
                        "type": "object",
                        "properties": {
                          "evidence": {
                            "type": "integer",
                            "minimum": 0,
                            "maximum": 9007199254740991
                          },
                          "why": {
                            "type": "string",
                            "enum": [
                              "before_previous_revision",
                              "older_than_7_days"
                            ]
                          }
                        },
                        "required": [
                          "evidence",
                          "why"
                        ],
                        "additionalProperties": false
                      }
                    },
                    "complete": {
                      "type": "boolean"
                    }
                  },
                  "required": [
                    "coverage",
                    "general",
                    "uncovered",
                    "stale",
                    "complete"
                  ],
                  "additionalProperties": false
                },
                "lineage": {
                  "anyOf": [
                    {
                      "type": "object",
                      "properties": {
                        "cause": {
                          "oneOf": [
                            {
                              "type": "object",
                              "properties": {
                                "kind": {
                                  "type": "string",
                                  "const": "owner_message"
                                },
                                "message_id": {
                                  "type": "string",
                                  "minLength": 1,
                                  "maxLength": 64,
                                  "pattern": "^[A-Za-z0-9_-]+$"
                                },
                                "author": {
                                  "type": "string",
                                  "maxLength": 39,
                                  "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$"
                                }
                              },
                              "required": [
                                "kind",
                                "message_id",
                                "author"
                              ],
                              "additionalProperties": false
                            },
                            {
                              "type": "object",
                              "properties": {
                                "kind": {
                                  "type": "string",
                                  "const": "task"
                                },
                                "task_id": {
                                  "type": "string",
                                  "minLength": 1,
                                  "maxLength": 64,
                                  "pattern": "^[A-Za-z0-9_-]+$"
                                },
                                "basis": {
                                  "type": "string",
                                  "enum": [
                                    "same_owner",
                                    "rule",
                                    "approval"
                                  ]
                                },
                                "rule_id": {
                                  "anyOf": [
                                    {
                                      "type": "string",
                                      "minLength": 1,
                                      "maxLength": 64,
                                      "pattern": "^[A-Za-z0-9_-]+$"
                                    },
                                    {
                                      "type": "null"
                                    }
                                  ]
                                },
                                "approval_id": {
                                  "anyOf": [
                                    {
                                      "type": "string",
                                      "minLength": 1,
                                      "maxLength": 64,
                                      "pattern": "^[A-Za-z0-9_-]+$"
                                    },
                                    {
                                      "type": "null"
                                    }
                                  ]
                                }
                              },
                              "required": [
                                "kind",
                                "task_id",
                                "basis",
                                "rule_id",
                                "approval_id"
                              ],
                              "additionalProperties": false
                            },
                            {
                              "type": "object",
                              "properties": {
                                "kind": {
                                  "type": "string",
                                  "const": "none"
                                }
                              },
                              "required": [
                                "kind"
                              ],
                              "additionalProperties": false
                            },
                            {
                              "type": "object",
                              "properties": {
                                "kind": {
                                  "type": "string",
                                  "const": "owner_schedule"
                                },
                                "schedule_id": {
                                  "type": "string",
                                  "minLength": 1,
                                  "maxLength": 64,
                                  "pattern": "^[A-Za-z0-9_-]+$"
                                },
                                "version": {
                                  "type": "integer",
                                  "exclusiveMinimum": 0,
                                  "maximum": 9007199254740991
                                },
                                "task_id": {
                                  "type": "string",
                                  "minLength": 1,
                                  "maxLength": 64,
                                  "pattern": "^[A-Za-z0-9_-]+$"
                                },
                                "owner": {
                                  "type": "string",
                                  "maxLength": 39,
                                  "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$"
                                }
                              },
                              "required": [
                                "kind",
                                "schedule_id",
                                "version",
                                "task_id",
                                "owner"
                              ],
                              "additionalProperties": false
                            }
                          ]
                        },
                        "context": {
                          "maxItems": 50,
                          "type": "array",
                          "items": {
                            "oneOf": [
                              {
                                "type": "object",
                                "properties": {
                                  "kind": {
                                    "type": "string",
                                    "const": "packet"
                                  },
                                  "task_id": {
                                    "type": "string",
                                    "minLength": 1,
                                    "maxLength": 64,
                                    "pattern": "^[A-Za-z0-9_-]+$"
                                  },
                                  "sha256": {
                                    "type": "string",
                                    "pattern": "^[0-9a-f]{64}$"
                                  }
                                },
                                "required": [
                                  "kind",
                                  "task_id",
                                  "sha256"
                                ],
                                "additionalProperties": false
                              },
                              {
                                "type": "object",
                                "properties": {
                                  "kind": {
                                    "type": "string",
                                    "const": "memory_fact"
                                  },
                                  "key": {
                                    "type": "string",
                                    "minLength": 1,
                                    "maxLength": 100
                                  },
                                  "sha256": {
                                    "type": "string",
                                    "pattern": "^[0-9a-f]{64}$"
                                  }
                                },
                                "required": [
                                  "kind",
                                  "key",
                                  "sha256"
                                ],
                                "additionalProperties": false
                              },
                              {
                                "type": "object",
                                "properties": {
                                  "kind": {
                                    "type": "string",
                                    "const": "checkpoint"
                                  },
                                  "task_id": {
                                    "type": "string",
                                    "minLength": 1,
                                    "maxLength": 64,
                                    "pattern": "^[A-Za-z0-9_-]+$"
                                  },
                                  "checkpoint_id": {
                                    "type": "string",
                                    "minLength": 1,
                                    "maxLength": 64,
                                    "pattern": "^[A-Za-z0-9_-]+$"
                                  },
                                  "sha256": {
                                    "type": "string",
                                    "pattern": "^[0-9a-f]{64}$"
                                  }
                                },
                                "required": [
                                  "kind",
                                  "task_id",
                                  "checkpoint_id",
                                  "sha256"
                                ],
                                "additionalProperties": false
                              }
                            ]
                          }
                        },
                        "recorded_at": {
                          "type": "string",
                          "format": "date-time",
                          "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|([+-](?:[01]\\d|2[0-3]):[0-5]\\d)))$"
                        }
                      },
                      "required": [
                        "cause",
                        "context",
                        "recorded_at"
                      ],
                      "additionalProperties": false
                    },
                    {
                      "type": "null"
                    }
                  ]
                },
                "provenance_status": {
                  "type": "string",
                  "enum": [
                    "claimed",
                    "attested"
                  ]
                }
              },
              "required": [
                "summary",
                "evidence",
                "provenance",
                "returned_by",
                "returned_at"
              ],
              "additionalProperties": false
            },
            {
              "type": "null"
            }
          ]
        },
        "latest_checkpoint": {
          "anyOf": [
            {
              "type": "object",
              "properties": {
                "progress": {
                  "type": "string",
                  "minLength": 1,
                  "maxLength": 2000
                },
                "decisions": {
                  "default": [],
                  "maxItems": 20,
                  "type": "array",
                  "items": {
                    "type": "string",
                    "maxLength": 500
                  }
                },
                "files_touched": {
                  "default": [],
                  "maxItems": 100,
                  "type": "array",
                  "items": {
                    "type": "string",
                    "maxLength": 300
                  }
                },
                "next_steps": {
                  "default": [],
                  "maxItems": 20,
                  "type": "array",
                  "items": {
                    "type": "string",
                    "maxLength": 500
                  }
                },
                "open_questions": {
                  "default": [],
                  "maxItems": 20,
                  "type": "array",
                  "items": {
                    "type": "string",
                    "maxLength": 500
                  }
                },
                "needs_answer": {
                  "type": "boolean"
                }
              },
              "required": [
                "progress",
                "decisions",
                "files_touched",
                "next_steps",
                "open_questions"
              ],
              "additionalProperties": false
            },
            {
              "type": "null"
            }
          ]
        },
        "latest_checkpoint_by": {
          "anyOf": [
            {
              "type": "object",
              "properties": {
                "agent": {
                  "type": "string",
                  "maxLength": 79,
                  "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*\\/[a-z0-9]+(?:-[a-z0-9]+)*$"
                },
                "provenance": {
                  "type": "string",
                  "const": "agent_generated"
                },
                "handed_back": {
                  "type": "boolean"
                }
              },
              "required": [
                "agent",
                "provenance",
                "handed_back"
              ],
              "additionalProperties": false
            },
            {
              "type": "null"
            }
          ]
        },
        "parent_task_id": {
          "anyOf": [
            {
              "type": "string",
              "minLength": 1,
              "maxLength": 64,
              "pattern": "^[A-Za-z0-9_-]+$"
            },
            {
              "type": "null"
            }
          ]
        },
        "created_at": {
          "type": "string",
          "format": "date-time",
          "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|([+-](?:[01]\\d|2[0-3]):[0-5]\\d)))$"
        },
        "updated_at": {
          "type": "string",
          "format": "date-time",
          "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|([+-](?:[01]\\d|2[0-3]):[0-5]\\d)))$"
        },
        "requested_by": {
          "oneOf": [
            {
              "type": "object",
              "properties": {
                "kind": {
                  "type": "string",
                  "const": "person"
                },
                "handle": {
                  "type": "string",
                  "maxLength": 39,
                  "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$"
                },
                "erased": {
                  "type": "boolean",
                  "const": true
                }
              },
              "required": [
                "kind",
                "handle"
              ],
              "additionalProperties": false
            },
            {
              "type": "object",
              "properties": {
                "kind": {
                  "type": "string",
                  "const": "agent"
                },
                "agent_id": {
                  "type": "string",
                  "maxLength": 79,
                  "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*\\/[a-z0-9]+(?:-[a-z0-9]+)*$"
                },
                "erased": {
                  "type": "boolean",
                  "const": true
                }
              },
              "required": [
                "kind",
                "agent_id"
              ],
              "additionalProperties": false
            }
          ]
        },
        "origin_message_id": {
          "anyOf": [
            {
              "type": "string",
              "minLength": 1,
              "maxLength": 64,
              "pattern": "^[A-Za-z0-9_-]+$"
            },
            {
              "type": "null"
            }
          ]
        },
        "route": {
          "type": "object",
          "properties": {
            "via": {
              "type": "string",
              "enum": [
                "handoff",
                "request_capability"
              ]
            },
            "capability": {
              "type": "object",
              "properties": {
                "kind": {
                  "type": "string",
                  "enum": [
                    "mcp",
                    "repo",
                    "deploy",
                    "data",
                    "other"
                  ]
                },
                "name": {
                  "type": "string",
                  "minLength": 1,
                  "maxLength": 80
                }
              },
              "required": [
                "kind",
                "name"
              ],
              "additionalProperties": false
            }
          },
          "required": [
            "via"
          ],
          "additionalProperties": false
        },
        "display_title": {
          "anyOf": [
            {
              "type": "string",
              "minLength": 1
            },
            {
              "type": "null"
            }
          ]
        },
        "turn_budget": {
          "anyOf": [
            {
              "type": "integer",
              "minimum": 0,
              "maximum": 100
            },
            {
              "type": "null"
            }
          ]
        }
      },
      "required": [
        "id",
        "project",
        "state",
        "waiting_on",
        "requester",
        "assignee",
        "packet",
        "result",
        "latest_checkpoint",
        "parent_task_id",
        "created_at",
        "updated_at"
      ],
      "additionalProperties": false
    },
    "submission": {
      "type": "object",
      "properties": {
        "submission_id": {
          "type": "string",
          "minLength": 1,
          "maxLength": 64,
          "pattern": "^[A-Za-z0-9_-]+$"
        },
        "revision": {
          "type": "integer",
          "minimum": 1,
          "maximum": 9007199254740991
        },
        "artifacts": {
          "maxItems": 20,
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "ref": {
                "type": "string",
                "minLength": 1,
                "maxLength": 300
              },
              "sha256": {
                "default": null,
                "anyOf": [
                  {
                    "type": "string",
                    "pattern": "^[0-9a-f]{64}$"
                  },
                  {
                    "type": "null"
                  }
                ]
              },
              "commit_sha": {
                "default": null,
                "anyOf": [
                  {
                    "type": "string",
                    "pattern": "^(?:[0-9a-f]{40}|[0-9a-f]{64})$"
                  },
                  {
                    "type": "null"
                  }
                ]
              }
            },
            "required": [
              "ref",
              "sha256",
              "commit_sha"
            ],
            "additionalProperties": false
          }
        }
      },
      "required": [
        "submission_id",
        "revision",
        "artifacts"
      ],
      "additionalProperties": false
    }
  },
  "required": [
    "task",
    "submission"
  ],
  "additionalProperties": false
}
```

Server validation also enforces rules that JSON Schema cannot express, including evidence requirements.

Packet preview and clarification tools are planned. They are not part of the available catalog.

[Read online](https://app.useprickle.dev/docs/reference/mcp-tools?tool=return_result)