API reference

Get an agent run

Reads the current or terminal status of one authenticated background run.

GET /v1/agent/{id}

Parameters

Request parameters

Name: id
In: path
Required: Yes
Type: string
Description: Agent-session UUID returned at creation.

Name: x-agent-session
In: header
Required: Yes
Type: string
Description: Session proof present only in the creation response.

Request cURL

curl --request GET "https://yep.com/api/v1/agent/$YEP_AGENT_SESSION_ID" \
  --header "Authorization: Bearer $YEP_API_KEY" \
  --header "x-agent-session: $YEP_AGENT_SESSION_SECRET"

Responses

Response statuses

Status: 200
Description: Current or terminal agent-session status.
Body: AgentRuntimeStatus

Status: 400
Description: Invalid request.
Body: PublicApiError

Status: 401
Description: API-key or session-proof authentication failed.
Body: PublicApiError

Status: 403
Description: The API key lacks agent permission.
Body: PublicApiError

Status: 404
Description: The session does not exist in the caller's scope.
Body: PublicApiError

Status: 429
Description: The request exceeded a rate boundary.
Body: PublicApiError

Status: 500
Description: The service could not safely complete the operation.
Body: PublicApiError

Status: 502
Description: The agent runtime returned an invalid response.
Body: PublicApiError

Status: 503
Description: The agent is temporarily unavailable.
Body: PublicApiError

Schemas

AgentRuntimeFailure

Product-facing agent failure after runtime metadata has crossed the policy boundary.

AgentRuntimeFailure fields

Field: class
Required: Yes
Type: AgentRuntimeFailureClass
Description: Stable runtime failure class.
Constraints

Field: message
Required: Yes
Type: string
Description: Sanitized target-owned explanation.
Constraints

Field: reason
Required: Yes
Type: null | ErrorReason
Description
Constraints

Field: recovery
Required: Yes
Type: null | ErrorRecovery
Description
Constraints

AgentRuntimeFailureClass

Closed portable runtime failure classes.

Request json

[
  "rate_limited",
  "timeout",
  "transport",
  "invalid_output",
  "rejected",
  "internal"
]

AgentRuntimeState

Portable runtime lifecycle values.

Request json

[
  "queued",
  "running",
  "succeeded",
  "failed"
]

AgentRuntimeStatus

Product-facing terminal or in-progress status returned by agent APIs.

AgentRuntimeStatus fields

Field: agent_session_id
Required: Yes
Type: string
Description: Non-secret execution correlation id from the signed runtime session.
Constraints

Field: error
Required: Yes
Type: null | AgentRuntimeFailure
Description
Constraints

Field: output
Required: Yes
Type: null | Report
Description
Constraints

Field: program_digest
Required: Yes
Type: string
Description: Pinned semantic program digest.
Constraints

Field: state
Required: Yes
Type: AgentRuntimeState
Description: Closed runtime lifecycle state.
Constraints

Field: usage
Required: Yes
Type: UsageReport
Description: Provider usage accumulated so far.
Constraints

ErrorCode

Machine-readable product API failure.

Request json

[
  "unauthenticated",
  "forbidden",
  "invalid_request",
  "not_found",
  "conflict",
  "payment_required",
  "too_many_requests",
  "upstream",
  "internal"
]

ErrorReason

Stable product API failure reason.

Request json

[
  "malformed_request",
  "authentication_required",
  "reauthentication_required",
  "permission_denied",
  "api_key_name_invalid",
  "spend_policy_invalid",
  "rate_policy_invalid",
  "provider_key_invalid",
  "provider_key_missing",
  "agent_model_not_allowed",
  "resource_not_found",
  "state_conflict",
  "insufficient_funds",
  "spend_limit_exceeded",
  "rate_limit_exceeded",
  "model_provider_rate_limited",
  "model_provider_overloaded",
  "dependency_unavailable",
  "internal_failure"
]

ErrorRecovery

Browser-safe recovery action selected by the authoritative product boundary.

ErrorRecovery alternatives

Variant: 1
Type: object

Variant: 2
Type: object

Variant: 3
Type: object

PublicApiError

Stable public error envelope for APIs whose reason vocabulary is extensible.

PublicApiError fields

Field: agent_session_id
Required: No
Type: string | null
Description: Agent execution correlation id, present after an invocation is admitted.
Constraints

Field: code
Required: Yes
Type: ErrorCode
Description: Closed status category suitable for program control flow.
Constraints

Field: message
Required: Yes
Type: string
Description: Safe diagnostic intended for operators, not program branching.
Constraints

Field: reason
Required: Yes
Type: string
Description: Extensible machine-readable detail; clients must accept unknown values.
Constraints

Field: recovery
Required: No
Type: null | ErrorRecovery
Description
Constraints

Field: validation
Required: No
Type: null | ValidationReport
Description
Constraints

Report

UsageReport

ValidationIssue

One actionable, privacy-safe contract violation.

ValidationIssue fields

Field: allowed_values
Required: No
Type: array | null
Description
Constraints: max items: 16

Field: code
Required: Yes
Type: string
Description: Stable, extensible machine-readable category.
Constraints: max length: 64

Field: path
Required: Yes
Type: string
Description: RFC 6901 pointer to the rejected location; empty means the root value.
Constraints: max length: 1024

Field: suggestion
Required: Yes
Type: string
Description: Code-owned instruction for correcting the request.
Constraints: max length: 512

ValidationReport

Bounded validation feedback shared by model, REST, and MCP boundaries.

ValidationReport fields

Field: contract
Required: Yes
Type: string
Description: Stable contract name, normally the published schema component name.
Constraints: max length: 128

Field: issues
Required: Yes
Type: ValidationIssue[]
Description: At most eight deterministic violations. Correct every issue before retrying.
Constraints: max items: 8

Field: truncated
Required: Yes
Type: boolean
Description: Whether more violations were omitted; retry after correcting the listed issues.
Constraints

Agent