FA-99751 / Tool call schema validation / Open access

Integer arguments are accepted as booleans · case 01

Integer arguments are accepted as booleans.

Verified by executionVariant 1 · 6 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Python numeric subtype behavior makes integer values pass a bool check.

THE FAILURE

Python numeric subtype behavior makes integer values pass a bool check.

Unsuccessful approach: Rejecting integers but also rejecting False still mishandles a valid boolean.

Case contract

A boolean field accepts only values whose exact type is bool; integer 0 and 1 are not booleans.

Why this case matters

Tool argument validation prevents malformed structured payloads from entering a deterministic downstream operation.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(value):
    return isinstance(value,int)
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('true',solve(True),True)
check('false',solve(False),True)
check('integer one',solve(1),False)
check('integer zero',solve(0),False)
check('string',solve('true'),False)
check('null',solve(None),False)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
true	`True`	`True`	Passed
false	`True`	`True`	Passed
integer one	`True`	`False`	Failed
integer zero	`True`	`False`	Failed
string	`False`	`False`	Passed
null	`False`	`False`	Passed

SHA-256 / 628444622a96b57e3dfe50c4cc92d11dccfeba6fecfa2078f6399d58b9c0ca11

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(value):
    return type(value) is bool and value is not False
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('true',solve(True),True)
check('false',solve(False),True)
check('integer one',solve(1),False)
check('integer zero',solve(0),False)
check('string',solve('true'),False)
check('null',solve(None),False)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
true	`True`	`True`	Passed
false	`False`	`True`	Failed
integer one	`False`	`False`	Passed
integer zero	`False`	`False`	Passed
string	`False`	`False`	Passed
null	`False`	`False`	Passed

SHA-256 / 58f2f7f202327793c3ccb3d38c95623e618bacadff8a83e68f4115564bbd82c6

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 6 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

Verification & scope

Self-contained toy JSON-like schema contract over in-memory Python values; no compatibility with a production schema standard or callable binding is claimed. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-30T16:48:27.615989+00:00.

Case digest / 896b0d81edbab96860762244614cd781a7c0ef1b45a900337a194de89cd652e3