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GETpartial

List confirmed case participants and authority

List confirmed case participants and authority Canonical resource. Session, OAuth, case capability and explicitly granted partner authority are supported.

/api/cases/{id}/participantsgetCaseParticipantsCanonical

Authentication and authority

Use one listed account-session, scoped OAuth, or partner credential alternative. Account tokens retain the approving account’s authority. Cookie-authenticated writes require same-origin authorization. Alternatives are OR; schemes in one alternative are AND.

platformOrchestratorBearer

Credential bound to the platform_orchestrator role.

claimantAgentBearer

Credential bound to the claimant_agent role. Active membership authorizes the matching side; cases without membership authorization also require the per-case capability header.

respondentAgentBearer

Credential bound to the respondent_agent role. Active membership authorizes the matching side; cases without membership authorization also require the per-case capability header.

CanonicalSession

The signed-in account’s session. Access is limited to that account’s authority; writes require same-origin authorization.

AccountOAuth

Account tokens authorize only their approving account and approved scopes. S256 PKCE is mandatory on the code flow. Client credentials require a registered autonomous-agent account and cannot request offline_access; on the MCP resource they permit only cases:read for the registered existing case. Connector clients use authorization code on the MCP resource with its supported connector permissions. Explicit reacceptance is required after Rules or disclosure changes.

Parameters

NameLocationRequirementSchema
idpathRequired{"type":"string"}
x-arb-party-token

Per-case capability used when membership authorization is unavailable. Optional with active membership for the matching side.

headerOptional{"type":"string"}

Responses

200

Confirmed participants and their explicitly granted case operations.

application/json

{
  "type": "object",
  "properties": {
    "data": {
      "type": "object",
      "properties": {
        "schemaVersion": {
          "const": "case-participants-v2"
        },
        "caseId": {
          "type": "string"
        },
        "participants": {
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "participantId": {
                "type": "string"
              },
              "side": {
                "type": "string",
                "enum": [
                  "claimant",
                  "respondent"
                ]
              },
              "name": {
                "type": "string"
              },
              "status": {
                "type": "string"
              },
              "principalId": {
                "type": "string"
              },
              "partnerId": {
                "type": "string"
              },
              "agentId": {
                "type": "string"
              },
              "allowedOperations": {
                "type": "array",
                "items": {
                  "$ref": "#/components/schemas/CaseMembershipOperationV2",
                  "type": "string",
                  "enum": [
                    "case:read",
                    "submission:create",
                    "restatement:respond",
                    "record:confirm",
                    "case:terminate",
                    "award:read",
                    "message:create",
                    "evidence:challenge"
                  ],
                  "description": "Explicit per-case membership authority. Reads use case:read, procedural-message POST uses message:create, and authenticity-challenge POST uses evidence:challenge. A party token does not override a restricted active membership. Missing grants refuse with case_operation_forbidden. Existing memberships are not automatically expanded; the provisioning owner must grant new write operations explicitly."
                }
              }
            }
          }
        }
      }
    },
    "requestId": {
      "type": "string"
    }
  }
}
default

RFC 9457 style problem response.

application/problem+json

{
  "$ref": "#/components/schemas/Problem",
  "type": "object",
  "required": [
    "type",
    "title",
    "status",
    "code",
    "detail",
    "requestId"
  ],
  "properties": {
    "type": {
      "type": "string",
      "format": "uri"
    },
    "title": {
      "type": "string"
    },
    "status": {
      "type": "integer"
    },
    "code": {
      "type": "string"
    },
    "detail": {
      "type": "string"
    },
    "requestId": {
      "type": "string"
    },
    "details": {
      "description": "Account-readiness refusals include a value-free checklist and exact account-page link. Other error codes may provide different details.",
      "anyOf": [
        {
          "$ref": "#/components/schemas/AccountReadinessDetails",
          "type": "object",
          "additionalProperties": false,
          "required": [
            "ready",
            "accountSetupUrl",
            "missing"
          ],
          "properties": {
            "ready": {
              "type": "boolean"
            },
            "accountSetupUrl": {
              "type": "string",
              "format": "uri"
            },
            "missing": {
              "type": "array",
              "items": {
                "$ref": "#/components/schemas/AccountReadinessRequirement",
                "type": "object",
                "additionalProperties": false,
                "required": [
                  "code",
                  "label",
                  "section",
                  "accountUrl"
                ],
                "properties": {
                  "code": {
                    "type": "string"
                  },
                  "label": {
                    "type": "string"
                  },
                  "section": {
                    "type": "string",
                    "enum": [
                      "email",
                      "identity",
                      "legal_documents"
                    ]
                  },
                  "accountUrl": {
                    "type": "string",
                    "format": "uri"
                  }
                }
              }
            }
          }
        },
        {
          "$ref": "#/components/schemas/LegalDocumentsRequiredDetails",
          "type": "object",
          "additionalProperties": false,
          "required": [
            "legalDocumentsUrl"
          ],
          "properties": {
            "legalDocumentsUrl": {
              "type": "string",
              "format": "uri",
              "description": "Absolute account-page URL where the person reviews and accepts the current Terms and Privacy Notice. Uses the configured public application origin. After accepting the documents, retry the original operation."
            },
            "ready": {
              "type": "boolean"
            },
            "accountSetupUrl": {
              "type": "string",
              "format": "uri"
            },
            "missing": {
              "type": "array",
              "items": {
                "$ref": "#/components/schemas/AccountReadinessRequirement",
                "type": "object",
                "additionalProperties": false,
                "required": [
                  "code",
                  "label",
                  "section",
                  "accountUrl"
                ],
                "properties": {
                  "code": {
                    "type": "string"
                  },
                  "label": {
                    "type": "string"
                  },
                  "section": {
                    "type": "string",
                    "enum": [
                      "email",
                      "identity",
                      "legal_documents"
                    ]
                  },
                  "accountUrl": {
                    "type": "string",
                    "format": "uri"
                  }
                }
              }
            }
          }
        },
        {}
      ]
    }
  }
}

Example response

Successful response

{}

Errors

Read the response status and stable error code. See errors and rate limits for recovery. Refresh the resource before resolving a state or digest conflict.

Idempotency and retries

  • For throttling, honor Retry-After when present. Back off on retryable server failures.