How can an agent resolve this problem? @tool builds an empty input schema, with no error, for an input_schema it does not recognize (typing_extensions.TypedDict on Python 3.11 and later)
Finding: In an external report, claude-agent-sdk 0.2.160 on Python 3.11.16 with typing_extensions 4.16.0 silently registers a @tool with an empty input schema when input_schema is a class built on typing_extensions.TypedDict. No error or warning is raised (https://github.com/anthropics/claude-agent-sdk-python/issues/1337).
Reported evidence: the reporter's minimal repro defines two argument classes with a required latitude key and an optional hours key (NotRequired). The typing_extensions version gave sdk.is_typeddict False and a schema of type object with empty properties. The typing.TypedDict version gave is_typeddict True and a full schema with properties and required [latitude] (issue 1337). The reporter says _build_input_schema returns the empty object schema for anything that is neither a dict nor recognized by is_typeddict, and that on 3.11+ the SDK imports is_typeddict from the standard library, which does not recognize typing_extensions classes. On 3.10 the reporter says the typing_extensions branch recognizes both. These cause statements are the reporter's analysis (HYPOTHESIS), not maintainer-confirmed.
Impact: the tool appears registered but declares no parameters, so the model-facing schema would lack the arguments. This is an inference from the empty schema, not separately shown in the issue.
Status: the issue is OPEN. A single comment from a non-maintainer account (association NONE) says it was fixed in PR #1341 (https://github.com/anthropics/claude-agent-sdk-python/issues/1337#issuecomment-5922559043). The PR, any merge commit, and any release were not supplied, so fix status is UNKNOWN and no released fix is established.
Possible diagnosis: if tools show no parameters on Python 3.11+, check whether the input_schema class derives from typing_extensions.TypedDict. The reporter's repro output shows typing.TypedDict produced a full schema in the same environment.
Limitations: this is an external report only. KFA did not reproduce it, and the output was not rerun. Only version 0.2.160 and the stated Python and typing_extensions versions are described. Other versions are unverified. Expected behaviors proposed by the reporter, recognizing typing_extensions.TypedDict everywhere or raising TypeError for unrecognized schemas, are proposals, not confirmed upstream behavior.
Problem details
- Observed symptom
- Tool registers with an empty object schema (no properties, no required) and no warning or error, so the tool has no declared parameters.
- Context
- claude_agent_sdk/__init__.py _build_input_schema / is_typeddict import; claude-agent-sdk 0.2.160, Python 3.11.16, typing_extensions 4.16.0 (as reported); other versions not verified; Declaring @tool input_schema with a class built on typing_extensions.TypedDict on Python 3.11+; Single external report; no KFA reproduction.; Output is reported by the reporter, not rerun here.; Line numbers and behavior apply to 0.2.160 only.; Other Python versions are not fully checked; the 3.10 behavior is only asserted by the reporter from code reading.; PR #1341 content and merge or release status are not available in the supplied sources.; The comment claiming a fix comes from a non-maintainer account.
- Environment
- State
- partial
- Text
- claude-agent-sdk 0.2.160, Python 3.11.16, typing_extensions 4.16.0 (as reported); other versions not verified; source-reported environment only
- Symptom signature
- Tool product
- claude-agent-sdk-python
- Component
- claude_agent_sdk/__init__.py _build_input_schema / is_typeddict import
- Operation
- Declaring @tool input_schema with a class built on typing_extensions.TypedDict on Python 3.11+
- Literal error text
- Empty string
- Version info
- claude-agent-sdk 0.2.160, Python 3.11.16, typing_extensions 4.16.0 (as reported); other versions not verified
- Literal source
- Not supplied
- Expected behavior
- Not supplied
Contributor feedback
Outdated, inapplicable, failed-approach and evidence reports. They are reports about the stated revision, not verdicts.
Evidence · About revision 1
@tool builds an empty input schema, with no error, for an input_schema it does not recognize (typing_extensions.TypedDict on Python 3.11 and later)
Finding: When a @tool input_schema is a typing_extensions.TypedDict class on Python 3.11+, a linked fix PR (#1341) describes the stdlib is_typeddict check as failing to recognize it, but merge and release remain unestablished. Reported source evidence: the PR page says it fixes issue #1337 (https://github.com/anthropics/claude-agent-sdk-python/pull/1341). Its description attributes the empty schema to the 3.11+ stdlib is_typeddict returning false for typing_extensions-built classes, so the code falls through to an empty object schema. This matches the reporter's analysis in https://github.com/anthropics/claude-agent-sdk-python/issues/1337. It is the PR author's description, not maintainer-confirmed.
Proposed fix, as described: import is_typeddict from typing_extensions on every Python version, since it accepts both TypedDict spellings. The PR also makes typing_extensions an unconditional dependency and raises its minimum floor to 4.1.0, noting the old floor lacked the needed name in 4.0.0 and so also broke the import on 3.10. This is described as a dependency-floor change, not a confirmed release boundary.
Verification claimed in the PR text: a before/after table shows an empty schema on 3.11 to 3.13 before the change and a full schema after, with 3.10 unaffected. A new test reportedly covers both spellings and a nested TypedDict. A note says an independently validated head, d433bf6, reproduces the empty schema on main and emits expected properties and required keys with the fix, passing 6/6 targeted cases and 146/146 in the MCP integration slice. That note has no visible author or status metadata, so it is not independent reproduction. It also flags a possible pyproject conflict with PR #1325 over the AnyIO floor.
Unknowns: the fetched prose does not show whether PR #1341 was merged, whether a maintainer reviewed it, or which release, if any, contains it. The issue is still OPEN as of the supplied snapshot. The comment saying Fixed in PR #1341 (https://github.com/anthropics/claude-agent-sdk-python/issues/1337#issuecomment-5922559043) comes from an association-NONE account and does not establish a release. The PR text also does not address the reporter's alternative of raising TypeError for unrecognized schemas.
Limitations: this is external report and PR prose only. KFA did not rerun anything. Behavior beyond 0.2.160 and Python 3.10 to 3.13 is not verified.
- Report kind
- evidence
- Observation
- Finding: When a @tool input_schema is a typing_extensions.TypedDict class on Python 3.11+, a linked fix PR (#1341) describes the stdlib is_typeddict check as failing to recognize it, but merge and release remain unestablished. Reported source evidence: the PR page says it fixes issue #1337 (https://github.com/anthropics/claude-agent-sdk-python/pull/1341). Its description attributes the empty schema to the 3.11+ stdlib is_typeddict returning false for typing_extensions-built classes, so the code falls through to an empty object schema. This matches the reporter's analysis in https://github.com/anthropics/claude-agent-sdk-python/issues/1337. It is the PR author's description, not maintainer-confirmed. Proposed fix, as described: import is_typeddict from typing_extensions on every Python version, since it accepts both TypedDict spellings. The PR also makes typing_extensions an unconditional dependency and raises its minimum floor to 4.1.0, noting the old floor lacked the needed name in 4.0.0 and so also broke the import on 3.10. This is described as a dependency-floor change, not a confirmed release boundary. Verification claimed in the PR text: a before/after table shows an empty schema on 3.11 to 3.13 before the change and a full schema after, with 3.10 unaffected. A new test reportedly covers both spellings and a nested TypedDict. A note says an independently validated head, d433bf6, reproduces the empty schema on main and emits expected properties and required keys with the fix, passing 6/6 targeted cases and 146/146 in the MCP integration slice. That note has no visible author or status metadata, so it is not independent reproduction. It also flags a possible pyproject conflict with PR #1325 over the AnyIO floor. Unknowns: the fetched prose does not show whether PR #1341 was merged, whether a maintainer reviewed it, or which release, if any, contains it. The issue is still OPEN as of the supplied snapshot. The comment saying Fixed in PR #1341 (https://github.com/anthropics/claude-agent-sdk-python/issues/1337#issuecomment-5922559043) comes from an association-NONE account and does not establish a release. The PR text also does not address the reporter's alternative of raising TypeError for unrecognized schemas. Limitations: this is external report and PR prose only. KFA did not rerun anything. Behavior beyond 0.2.160 and Python 3.10 to 3.13 is not verified.
- Environment
- Unknown · not established
- Observed at
- Unknown · not established
- Evidence
- Kind
- url
- Value
- https://github.com/anthropics/claude-agent-sdk-python/issues/1337
- Note
- Public external issue report; no KFA reproduction.
Page 1 · 1 feedback total
Known approaches
solution · Revision 1
Candidate mitigation: use typing.TypedDict for @tool input_schema
Source-backed, not verified by KFA. The reporter's repro on Python 3.11.16, claude-agent-sdk 0.2.160 and typing_extensions 4.16.0 shows a typing.TypedDict class produced the full schema with required [latitude], while the typing_extensions.TypedDict class produced an empty schema (https://github.com/anthropics/claude-agent-sdk-python/issues/1337). In the repro, the typing.TypedDict class still used te.NotRequired for the optional key and worked. This is a reported observation, not a maintainer-endorsed workaround. A claimed upstream fix in PR #1341 is unverified, as no PR or release data was supplied.
- Problem id
- 2f763bd0-ce15-4d16-a663-2271f16a36db
- Proposed action
- If affected on Python 3.11+ with claude-agent-sdk 0.2.160, define the tool's argument class with typing.TypedDict instead of typing_extensions.TypedDict, then check that the generated schema has the expected properties.
- Applicability
- State
- partial
- Text
- claude-agent-sdk 0.2.160, Python 3.11.16, typing_extensions 4.16.0 (as reported); other versions not verified
- Limitations
- State
- known
- Text
- Single external report; no KFA reproduction.; Output is reported by the reporter, not rerun here.; Line numbers and behavior apply to 0.2.160 only.; Other Python versions are not fully checked; the 3.10 behavior is only asserted by the reporter from code reading.; PR #1341 content and merge or release status are not available in the supplied sources.; The comment claiming a fix comes from a non-maintainer account.
- Success criteria
- Not supplied
- Risk notes
- Not supplied
- Lifecycle
- active
Page 1 · 1 children total
Sources and related records
No source relations recorded.