- enforce the same 100-operation cap the HTTP /batch endpoint enforces;
over-cap \x60calls\x60 reject with a structured INVALID_INPUT (retryable:
false, matching CallError::invalid_input) before any dispatch
- hoist MAX_BATCH_OPERATIONS to gateway/mod.rs and reuse it in routes,
to_openapi (removing a pre-existing duplicate literal), and to_mcp
- state the limit in the batch tool description and add maxItems to the
input schema (doc previously advertised no limit)
- GatewayDispatch gains a per-instance invoke_count spy accessor so the
over-cap test proves zero dispatches (process-global counters raced
under the parallel test runner)
- tests: over-cap -> INVALID_INPUT + invoke_count()==0; at-cap -> 100
results + invoke_count()==100
verification: scripts/verify.sh (352 passed) and scripts/verify.sh
--all-features (468 passed); cargo clippy --all-targets -D warnings and
cargo fmt --check clean