YeonGyu-Kim 7abefcca1f feat: auto-recover from Anthropic assistant message prefill errors
When Anthropic models reject requests with 'This model does not support
assistant message prefill', detect this as a recoverable error type and
automatically send 'Continue' once to resume the conversation.

Extends session-recovery hook with new 'assistant_prefill_unsupported'
error type. The existing session.error handler in index.ts already sends
'continue' after successful recovery, so no additional logic needed.
2026-02-08 13:16:16 +09:00

281 lines
9.0 KiB
TypeScript

import { describe, expect, it } from "bun:test"
import { detectErrorType } from "./index"
describe("detectErrorType", () => {
describe("thinking_block_order errors", () => {
it("should detect 'first block' error pattern", () => {
// given an error about thinking being the first block
const error = {
message: "messages.0: thinking block must not be the first block",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order
expect(result).toBe("thinking_block_order")
})
it("should detect 'must start with' error pattern", () => {
// given an error about message must start with something
const error = {
message: "messages.5: thinking must start with text or tool_use",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order
expect(result).toBe("thinking_block_order")
})
it("should detect 'preceeding' error pattern", () => {
// given an error about preceeding block
const error = {
message: "messages.10: thinking requires preceeding text block",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order
expect(result).toBe("thinking_block_order")
})
it("should detect 'expected/found' error pattern", () => {
// given an error about expected vs found
const error = {
message: "messages.3: thinking block expected text but found tool_use",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order
expect(result).toBe("thinking_block_order")
})
it("should detect 'final block cannot be thinking' error pattern", () => {
// given an error about final block cannot be thinking
const error = {
message:
"messages.125: The final block in an assistant message cannot be thinking.",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order
expect(result).toBe("thinking_block_order")
})
it("should detect 'final block' variant error pattern", () => {
// given an error mentioning final block with thinking
const error = {
message:
"messages.17: thinking in the final block is not allowed in assistant messages",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order
expect(result).toBe("thinking_block_order")
})
it("should detect 'cannot be thinking' error pattern", () => {
// given an error using 'cannot be thinking' phrasing
const error = {
message:
"messages.219: The last block in an assistant message cannot be thinking content",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order
expect(result).toBe("thinking_block_order")
})
})
describe("tool_result_missing errors", () => {
it("should detect tool_use/tool_result mismatch", () => {
// given an error about tool_use without tool_result
const error = {
message: "tool_use block requires corresponding tool_result",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return tool_result_missing
expect(result).toBe("tool_result_missing")
})
})
describe("thinking_disabled_violation errors", () => {
it("should detect thinking disabled violation", () => {
// given an error about thinking being disabled
const error = {
message:
"thinking is disabled for this model and cannot contain thinking blocks",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_disabled_violation
expect(result).toBe("thinking_disabled_violation")
})
})
describe("assistant_prefill_unsupported errors", () => {
it("should detect assistant message prefill error from direct message", () => {
//#given an error about assistant message prefill not being supported
const error = {
message: "This model does not support assistant message prefill. The conversation must end with a user message.",
}
//#when detectErrorType is called
const result = detectErrorType(error)
//#then should return assistant_prefill_unsupported
expect(result).toBe("assistant_prefill_unsupported")
})
it("should detect assistant message prefill error from nested error object", () => {
//#given an Anthropic API error with nested structure matching the real error format
const error = {
error: {
type: "invalid_request_error",
message: "This model does not support assistant message prefill. The conversation must end with a user message.",
},
}
//#when detectErrorType is called
const result = detectErrorType(error)
//#then should return assistant_prefill_unsupported
expect(result).toBe("assistant_prefill_unsupported")
})
it("should detect error with only 'conversation must end with a user message' fragment", () => {
//#given an error containing only the user message requirement
const error = {
message: "The conversation must end with a user message.",
}
//#when detectErrorType is called
const result = detectErrorType(error)
//#then should return assistant_prefill_unsupported
expect(result).toBe("assistant_prefill_unsupported")
})
it("should detect error with only 'assistant message prefill' fragment", () => {
//#given an error containing only the prefill mention
const error = {
message: "This model does not support assistant message prefill.",
}
//#when detectErrorType is called
const result = detectErrorType(error)
//#then should return assistant_prefill_unsupported
expect(result).toBe("assistant_prefill_unsupported")
})
})
describe("unrecognized errors", () => {
it("should return null for unrecognized error patterns", () => {
// given an unrelated error
const error = {
message: "Rate limit exceeded",
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return null
expect(result).toBeNull()
})
it("should return null for empty error", () => {
// given an empty error
const error = {}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return null
expect(result).toBeNull()
})
it("should return null for null error", () => {
// given a null error
const error = null
// when detectErrorType is called
const result = detectErrorType(error)
// then should return null
expect(result).toBeNull()
})
})
describe("nested error objects", () => {
it("should detect error in data.error.message path", () => {
// given an error with nested structure
const error = {
data: {
error: {
message:
"messages.163: The final block in an assistant message cannot be thinking.",
},
},
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order
expect(result).toBe("thinking_block_order")
})
it("should detect error in error.message path", () => {
// given an error with error.message structure
const error = {
error: {
message: "messages.169: final block cannot be thinking",
},
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order
expect(result).toBe("thinking_block_order")
})
it("should detect thinking_block_order even when error message contains tool_use/tool_result in docs URL", () => {
// given Anthropic's extended thinking error with tool_use/tool_result in the documentation text
const error = {
error: {
type: "invalid_request_error",
message:
"messages.1.content.0.type: Expected `thinking` or `redacted_thinking`, but found `text`. " +
"When `thinking` is enabled, a final `assistant` message must start with a thinking block " +
"(preceeding the lastmost set of `tool_use` and `tool_result` blocks). " +
"We recommend you include thinking blocks from previous turns.",
},
}
// when detectErrorType is called
const result = detectErrorType(error)
// then should return thinking_block_order (NOT tool_result_missing)
expect(result).toBe("thinking_block_order")
})
})
})