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Merged
rekram1-node merged 1 commit into from
Oct 6, 2026
+5 −28
Merged

fix(core): drop tool name and namespace length caps #53586

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4 changes: 2 additions & 2 deletions packages/core/src/tool.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -308,7 +308,7 @@ function registrationError(tool: Tool.Info) {
if (error) return error
}
const name = normalizedName(tool)
if (!/^[A-Za-z0-9_-]{1,128}$/.test(name)) return new RegistrationError({ name, message: `Invalid tool name: ${name}` })
if (!/^[A-Za-z0-9_-]+$/.test(name)) return new RegistrationError({ name, message: `Invalid tool name: ${name}` })
const id = effectiveName(tool)
if (tool.options?.codemode === false && id === "execute")
return new RegistrationError({ name: id, message: 'Tool name "execute" is reserved for CodeMode' })
Expand All @@ -321,7 +321,7 @@ function registrationError(tool: Tool.Info) {
}

function namespaceError(name: string) {
if (name.split(".").every((segment) => /^[A-Za-z0-9_-]{1,64}$/.test(segment))) return
if (name.split(".").every((segment) => /^[A-Za-z0-9_-]+$/.test(segment))) return
return new RegistrationError({ name, message: `Invalid tool namespace: ${JSON.stringify(name)}` })
}

Expand Down
7 changes: 3 additions & 4 deletions packages/core/test/mcp.test.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -2106,7 +2106,7 @@ test("serializes concurrent MCP lifecycle operations", async () => {
)
})

testEffect(Layer.empty).live("isolates invalid MCP tools and preserves plugin transforms through catalog updates", () =>
testEffect(Layer.empty).live("preserves plugin transforms through MCP catalog updates", () =>
Effect.gen(function* () {
const tool = (server: string, name: string, description = name) =>
({
Expand All @@ -2117,8 +2117,7 @@ testEffect(Layer.empty).live("isolates invalid MCP tools and preserves plugin tr
inputSchema: { type: "object", properties: {} },
}) satisfies Mcp.Tool
const healthy = [tool("demo", "search"), tool("other", "lookup")]
const namespace = tool("x".repeat(65), "lookup")
const catalog = yield* Ref.make([tool("demo", "x".repeat(129)), ...healthy, namespace])
const catalog = yield* Ref.make(healthy)

yield* Effect.gen(function* () {
const registry = yield* Tool.Service
Expand Down Expand Up @@ -2147,7 +2146,7 @@ testEffect(Layer.empty).live("isolates invalid MCP tools and preserves plugin tr
editor.remove("repaired_lookup")
})

yield* Ref.set(catalog, [tool("demo", "y".repeat(129)), ...healthy, tool("demo", "added"), namespace])
yield* Ref.set(catalog, [...healthy, tool("demo", "added")])
yield* bus.publish(McpEvent.ToolsChanged, { server: "demo" })
yield* waitForTool(registry, "demo_added")
expect((yield* toolDefinitions(registry)).map((tool) => tool.name)).toEqual([
Expand Down
22 changes: 0 additions & 22 deletions packages/core/test/tool-registry.test.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -329,7 +329,6 @@ describe("Tool", () => {
{
before: make(),
"": make(),
["x".repeat(129)]: make(),
"echo.tool": constant("first"),
echo_tool: constant("last"),
execute: make(),
Expand All @@ -346,27 +345,6 @@ describe("Tool", () => {
}),
)

it.effect("registers 128-character MCP tool names in Code Mode", () =>
Effect.gen(function* () {
const service = yield* Tool.Service
const name = "x".repeat(128)
yield* transform(service, { [name]: make(), ["x".repeat(129)]: make() }, { namespace: "cloudflare" })

const snapshot = yield* service.snapshot()
expect(codeModeListings(snapshot.codeModeCatalog!).map((tool) => tool.path)).toEqual([`cloudflare.${name}`])
const result = yield* snapshot.execute({
...call("execute"),
call: {
type: "tool-call",
id: "call-long-mcp-name",
name: "execute",
input: { code: `return (await tools.cloudflare[${JSON.stringify(name)}]({ text: "hello" })).text` },
},
})
expect(result.content).toEqual([{ type: "text", text: "hello" }])
}),
)

it.effect("executes native tools without requiring letter-leading names or namespace segments", () =>
Effect.gen(function* () {
const service = yield* Tool.Service
Expand Down
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