fix(core): allow load_toolset strict success when all params are used

[hsusul]

Summary

• Fixes ToolboxClient.load_toolset(..., strict=True) incorrectly rejecting loads where every provided auth token / bound parameter is used by every tool.
• Root cause: used-key accumulation ran only in the non-strict branch, so the final toolset-level unused-requirement check always saw empty overall-used sets under strict=True.
• Adds async and sync regression coverage for the documented strict success path, while keeping existing strict/non-strict failure tests.

🛠️ Fixes #734

Problem

With a mocked toolset containing a single tool that declares param_P:

await client.load_toolset(
    bound_params={"param_P": "some_value"},
    strict=True,
)

Before: raised

ValueError: Validation failed for toolset 'default': unused bound parameters could not be applied to any tool: param_P.

even though the tool used param_P. The same false failure occurred for fully used auth token getters.

After: loading succeeds, matching the strict docstring (fail only when any tool fails to use all provided params/tokens).

No GitHub issue was required for permissions reasons beyond standard contribution flow; issue #734 was filed to satisfy the PR template's issue-first checklist.

Root cause

In ToolboxClient.load_toolset, per-tool usage was recorded only in the else (non-strict) branch:

if strict:
    validate_unused_requirements(...)  # per-tool
else:
    overall_used_auth_keys.update(...)
    overall_used_bound_params.update(...)

validate_unused_requirements(..., overall_used_*, is_toolset=True)  # always runs

Under strict=True, overall_used_* stayed empty, so the final toolset check treated every provided key as unused.

Minimal implementation

Always update overall_used_auth_keys / overall_used_bound_params, then still run the per-tool strict check. Non-strict semantics are unchanged. Sync client inherits the fix via ToolboxSyncClient.load_toolset.

Tests

• test_load_toolset_strict_with_fully_used_bound_param_success
• test_load_toolset_strict_with_fully_used_auth_success
• test_sync_load_toolset_strict_with_fully_used_bound_param_success
• Existing strict partial-use and non-strict unused failure tests still pass

Validation

From packages/toolbox-core with pip install -e .[test] (Python 3.12):

• python -m pytest tests/test_client.py::TestValidation tests/test_sync_client.py::test_sync_load_toolset_strict_with_fully_used_bound_param_success -v → 9 passed
• python -m pytest tests/ --ignore=tests/test_e2e.py --ignore=tests/test_sync_e2e.py --ignore=tests/test_e2e_mcp.py --ignore=tests/conformance -q --cov=src/toolbox_core --cov-fail-under=90 → 478 passed, coverage 91.74%
• black --check . → pass
• isort --check . → pass
• MYPYPATH='./src' mypy --install-types --non-interactive -p toolbox_core → pass
• git diff --check → pass

Live Toolbox / GCP integration tests were not run (mocked unit coverage is sufficient for this client validation bug).

Adapter compatibility

No adapter changes. LangChain / LlamaIndex / ADK call into the same core load_toolset path and inherit the corrected strict behavior.

Non-goals

• Changing strict vs non-strict semantics beyond restoring the documented success path
• MCP isError handling, schema conversion, or ADK auth lifecycle (separate candidates)
• Dependency upgrades or docs-only changes

Test plan

• Unit regression for strict success (bound params + auth) on async client
• Unit regression for strict success on sync client
• Existing strict/non-strict unused validation tests still pass
• Lint (black, isort) and mypy for toolbox_core
• Maintainer-triggered CI (tests: run label / /gcbrun if needed for fork PRs)

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[anubhav756]

Can we also add tests for auth params as well just like in async client?

[anubhav756]

Can we also add tests for auth params as well just like in async client?

[anubhav756]

Can we have more than 1 tool here for better coverage?

[anubhav756]

/gcbrun

[hsusul]

Updated! I've updated the strict=True test cases in both test_client.py and test_sync_client.py to include multiple tools in the toolset for better coverage, as well as added tests for auth parameters on the sync client. Thanks!

[anubhav756]

/gcbrun