* test: drop the cwd-relative sys.path.insert calls from the test suite
TQ003 stands at 1,077 across 1,058 files, and 1,015 of them are the same shape:
sys.path.insert(0, os.path.abspath("../..")) and its deeper siblings. The
argument resolves against the working directory rather than the file, so from
the repo root, where every job runs pytest, it inserts the directory two levels
above the checkout. It has never pointed at litellm. The package is installed
into the environment anyway, which is what actually makes the import work, and
what the rule's message has said all along.
Removing them leaves 1,634 imports of sys and os with no remaining reference,
and those go too, except where another test module imports the name back out of
the file. The rest of TQ003 is 62 call sites that resolve against __file__ or a
variable, which are a different question and are left alone.
Collection is identical either way: 45,871 tests and the same 51 pre-existing
collection errors before and after, and ruff reports no new undefined name.
* test: drop the duplicate imports the sys.path sweep exposed to F811
* test(pre-call-utils): restore the os import the new bedrock tests need
Two review findings, both a chat-vs-messages divergence.
transform_mcp_tool_to_anthropic_tool sent the MCP inputSchema to Anthropic almost
as-is, while the chat path (_map_tool_helper) coerces the type to object, inlines
legacy definitions with unpack_legacy_defs, and allow-lists keys to
AnthropicInputSchema. So a tool whose schema carried $schema, legacy definitions
or oneOf worked on /chat/completions and 400d on /v1/messages; a clean-schema
server hid it. Both paths now run the same sanitize_input_schema_for_anthropic,
extracted next to unpack_legacy_defs so they cannot drift again, and the chat
path is refactored onto it rather than keeping its own copy.
buildMcpToolBlocks percent-encoded the server and toolset names inside
litellm_proxy/mcp/... urls, but the gateway resolves the name with a raw
server_url.split("/")[-1] and never url-decodes, so a name with a space failed
lookup. The already-working chat path does not encode; the shared builder now
matches it.
Tests pin both: reverting the transform to the unfiltered schema fails, and
re-adding encodeURIComponent fails the builder test.
MCP tool calling worked on /v1/chat/completions and /v1/responses but not on
/v1/messages. Those are the only two surfaces with an MCP gateway entry point,
so a litellm_proxy MCP reference reached Anthropic verbatim inside tools and the
API rejected the request with "Input tag 'mcp' found using 'type' does not match
any of the expected tags". The playground never surfaced this because it dropped
the reference before sending, and disabled the MCP selector for the endpoint.
Add the third entry point in anthropic_messages_handler, ahead of the provider
branch so it covers the native path and both bridges from one place. The gateway
expands the reference against the caller's own credentials and access control,
which is the whole point of routing it through litellm rather than handing the
url to the provider.
/v1/messages needs Anthropic's own tool shape, so transform_mcp_tool_to_anthropic_tool
joins the OpenAI chat and Responses transforms alongside it. The tool loop speaks
tool_use and tool_result rather than OpenAI tool_calls, and reuses the existing
FakeAnthropicMessagesStreamIterator to re-stream the result, the same pattern the
websearch interception already uses on this route. Argument extraction moves into
the shared extractor: an Anthropic tool_use block carries its arguments under
`input`, and reading only `arguments` failed silently, executing the tool with
every argument dropped.
On the frontend the request builder declared selectedMCPTools and never read it,
so no tools key was ever sent. Wire it through a shared block builder and add the
endpoint to MCP_SUPPORTED_ENDPOINTS, which is what greys the selector out.
Resolves LIT-4517
Resolves LIT-4518
