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fix: force additionalProperties false for strict mode compatibility #10210

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Merged
cte merged 1 commit into from
Dec 19, 2025
Merged

fix: force additionalProperties false for strict mode compatibility #10210

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8 changes: 5 additions & 3 deletions src/core/prompts/tools/native-tools/__tests__/mcp_server.spec.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -155,11 +155,12 @@ describe("getMcpServerTools", () => {
const result = getMcpServerTools(mockHub as McpHub)

expect(result).toHaveLength(1)
// additionalProperties: false should only be on the root object type, not on primitive types
expect(getFunction(result[0]).parameters).toEqual({
type: "object",
properties: {
requiredField: { type: "string", additionalProperties: false },
optionalField: { type: "number", additionalProperties: false },
requiredField: { type: "string" },
optionalField: { type: "number" },
},
additionalProperties: false,
required: ["requiredField"],
Expand All @@ -183,10 +184,11 @@ describe("getMcpServerTools", () => {
const result = getMcpServerTools(mockHub as McpHub)

expect(result).toHaveLength(1)
// additionalProperties: false should only be on the root object type, not on primitive types
expect(getFunction(result[0]).parameters).toEqual({
type: "object",
properties: {
optionalField: { type: "string", additionalProperties: false },
optionalField: { type: "string" },
},
additionalProperties: false,
})
Expand Down
39 changes: 19 additions & 20 deletions src/utils/__tests__/json-schema.spec.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -10,10 +10,10 @@ describe("normalizeToolSchema", () => {

const result = normalizeToolSchema(input)

// additionalProperties should NOT be added to non-object types (string, null)
expect(result).toEqual({
anyOf: [{ type: "string" }, { type: "null" }],
description: "Optional field",
additionalProperties: false,
})
})

Expand All @@ -26,11 +26,11 @@ describe("normalizeToolSchema", () => {

const result = normalizeToolSchema(input)

// additionalProperties should NOT be added to array or primitive types
expect(result).toEqual({
anyOf: [{ type: "array" }, { type: "null" }],
items: { type: "string", additionalProperties: false },
items: { type: "string" },
description: "Optional array",
additionalProperties: false,
})
})

Expand All @@ -42,10 +42,10 @@ describe("normalizeToolSchema", () => {

const result = normalizeToolSchema(input)

// additionalProperties should NOT be added to string type
expect(result).toEqual({
type: "string",
description: "Required field",
additionalProperties: false,
})
})

Expand All @@ -64,14 +64,14 @@ describe("normalizeToolSchema", () => {

const result = normalizeToolSchema(input)

// additionalProperties: false should ONLY be on the object type, not on primitives
expect(result).toEqual({
type: "object",
properties: {
name: { type: "string", additionalProperties: false },
name: { type: "string" },
optional: {
anyOf: [{ type: "string" }, { type: "null" }],
description: "Optional nested field",
additionalProperties: false,
},
},
required: ["name"],
Expand All @@ -96,21 +96,20 @@ describe("normalizeToolSchema", () => {

const result = normalizeToolSchema(input)

// additionalProperties: false should ONLY be on object types
expect(result).toEqual({
type: "array",
items: {
type: "object",
properties: {
path: { type: "string", additionalProperties: false },
path: { type: "string" },
line_ranges: {
anyOf: [{ type: "array" }, { type: "null" }],
items: { type: "integer", additionalProperties: false },
additionalProperties: false,
items: { type: "integer" },
},
},
additionalProperties: false,
},
additionalProperties: false,
})
})

Expand Down Expand Up @@ -162,18 +161,18 @@ describe("normalizeToolSchema", () => {

const result = normalizeToolSchema(input)

// additionalProperties: false should ONLY be on object types, not on null or primitive types
expect(result).toEqual({
anyOf: [
{
type: "object",
properties: {
optional: { anyOf: [{ type: "string" }, { type: "null" }], additionalProperties: false },
optional: { anyOf: [{ type: "string" }, { type: "null" }] },
},
additionalProperties: false,
},
{ type: "null", additionalProperties: false },
{ type: "null" },
],
additionalProperties: false,
})
})

Expand All @@ -183,7 +182,9 @@ describe("normalizeToolSchema", () => {
expect(normalizeToolSchema(123 as any)).toBe(123)
})

it("should transform additionalProperties when it is a schema object", () => {
it("should force additionalProperties to false for object types even when set to a schema", () => {
// For strict mode compatibility, we MUST force additionalProperties: false
// even when the original schema allowed arbitrary properties
const input = {
type: "object",
additionalProperties: {
Expand All @@ -193,13 +194,11 @@ describe("normalizeToolSchema", () => {

const result = normalizeToolSchema(input)

// The original additionalProperties schema is replaced with false for strict mode
expect(result).toEqual({
type: "object",
properties: {},
additionalProperties: {
anyOf: [{ type: "string" }, { type: "null" }],
additionalProperties: false,
},
additionalProperties: false,
})
})

Expand Down Expand Up @@ -276,11 +275,11 @@ describe("normalizeToolSchema", () => {

const result = normalizeToolSchema(input)

// additionalProperties should NOT be added to string types
expect(result).toEqual({
type: "string",
format: "date-time",
description: "Timestamp",
additionalProperties: false,
})
})

Expand Down Expand Up @@ -335,10 +334,10 @@ describe("normalizeToolSchema", () => {

const result = normalizeToolSchema(input)

// additionalProperties should NOT be added to string types
expect(result).toEqual({
type: "string",
description: "URL field",
additionalProperties: false,
})
expect(result.format).toBeUndefined()
})
Expand Down
20 changes: 18 additions & 2 deletions src/utils/json-schema.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -110,7 +110,8 @@ const NormalizedToolSchemaInternal: z.ZodType<Record<string, unknown>, z.ZodType
properties: z.record(z.string(), NormalizedToolSchemaInternal).optional(),
items: z.union([NormalizedToolSchemaInternal, z.array(NormalizedToolSchemaInternal)]).optional(),
required: z.array(z.string()).optional(),
additionalProperties: z.union([z.boolean(), NormalizedToolSchemaInternal]).default(false),
// Don't set default here - we'll handle it conditionally in the transform
additionalProperties: z.union([z.boolean(), NormalizedToolSchemaInternal]).optional(),
description: z.string().optional(),
default: z.unknown().optional(),
enum: z.array(JsonSchemaEnumValueSchema).optional(),
Expand All @@ -132,9 +133,13 @@ const NormalizedToolSchemaInternal: z.ZodType<Record<string, unknown>, z.ZodType
})
.passthrough()
.transform((schema) => {
const { type, required, properties, format, ...rest } = schema
const { type, required, properties, additionalProperties, format, ...rest } = schema
const result: Record<string, unknown> = { ...rest }

// Determine if this schema represents an object type
const isObjectType =
type === "object" || (Array.isArray(type) && type.includes("object")) || properties !== undefined

// If type is an array, convert to anyOf format (JSON Schema 2020-12)
if (Array.isArray(type)) {
result.anyOf = type.map((t) => ({ type: t }))
Expand Down Expand Up @@ -164,6 +169,17 @@ const NormalizedToolSchemaInternal: z.ZodType<Record<string, unknown>, z.ZodType
result.properties = {}
}

// Only add additionalProperties for object-type schemas
// Adding it to primitive types (string, number, etc.) is invalid JSON Schema
if (isObjectType) {
// For strict mode compatibility, we MUST set additionalProperties to false
// Even if the original schema had {} (any) or true, we force false because
// OpenAI/OpenRouter strict mode rejects schemas with additionalProperties != false
// The original schema intent (allowing arbitrary properties) is incompatible with strict mode
result.additionalProperties = false
}
// For non-object types, don't include additionalProperties at all

return result
}),
)
Expand Down
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