fix: WASM tool schema advertisement for exported typed schemas by hanakannzashi · Pull Request #1348 · nearai/ironclaw

hanakannzashi · 2026-03-18T05:56:44Z

Summary

Fix WASM tool schema advertisement so small typed schemas exported by the component are exposed directly to the LLM instead of always falling back to a permissive {} schema.
Keep the existing compact-schema behavior for large exported schemas by retaining the permissive fallback plus tool_info hint when the exported schema is too large.
Update WASM loader warnings so they correctly state that exported WASM metadata/schema will be used when description or parameters are missing from the capabilities sidecar.
This fixes Brave web-search behavior where the agent previously saw only {} and repeatedly called the tool without the required query field.

Change Type

Linked Issue

#1303

Validation

cargo fmt
cargo clippy --all --benches --tests --examples --all-features
Relevant tests pass: cargo check -q, cargo test -q test_advertised_schema_stays_permissive_until_sidecar_override --lib, cargo test -q test_large_exported_schema_stays_permissive_for_advertising --lib
Manual testing: verified local Brave web-search regression end-to-end; after the fix the agent successfully called the Brave WASM tool with real search parameters and completed a search, instead of repeatedly calling it with {} and failing on missing query

Security Impact

None.

Database Impact

None.

Blast Radius

Touches WASM tool schema advertisement and loader warning behavior. Regressions could affect how WASM tools are exposed to the LLM, especially tools with large exported schemas that should still stay compact.

Rollback Plan

Revert the WASM schema advertisement change in src/tools/wasm/wrapper.rs and the warning text updates in src/tools/wasm/loader.rs to restore the previous behavior.

Review track: B

gemini-code-assist · 2026-03-18T05:56:57Z

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly improves the interaction between the agent and WASM tools by refining how tool schemas are advertised to the Language Model. It ensures that tools with small, well-defined schemas are presented accurately, allowing the agent to make precise calls, while larger schemas still provide necessary hints for discovery. This change directly addresses and fixes a critical regression in the Brave web-search functionality, making the agent's tool usage more robust and effective.

Highlights

WASM Tool Schema Advertisement: Fixed WASM tool schema advertisement to expose small typed schemas directly to the LLM, preventing a fallback to a permissive {} schema.
Large Schema Handling: Maintained the existing compact-schema behavior for large exported schemas by retaining the permissive fallback plus a tool_info hint.
WASM Loader Warnings: Updated WASM loader warnings to correctly state that exported WASM metadata/schema will be used when description or parameters are missing from the capabilities sidecar.
Brave Web Search Fix: Resolved an issue with Brave web-search where the agent previously saw only {} and repeatedly called the tool without the required query field.

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gemini-code-assist

Code Review

This pull request correctly fixes an issue where WASM tool schemas were not being advertised properly to the LLM, leading to incorrect tool calls. The approach of advertising small schemas directly while falling back to a permissive schema for large ones is sound. The new test cases provide good coverage for this new logic. I have one suggestion to improve the clarity of a test name.

hanakannzashi · 2026-03-18T10:04:38Z

Same PR #1352

henrypark133

Review: WASM tool schema advertisement — overlaps with #1352

Thanks for the contribution! Unfortunately this PR overlaps almost entirely with #1352 (G7CNF), which implements the same behavior (advertise typed WASM schemas directly to the LLM when small enough) and has already been approved.

Both PRs modify the same lines in src/tools/wasm/wrapper.rs and src/tools/wasm/loader.rs. If #1352 lands first, this will create merge conflicts.

One thing your PR gets right that #1352 doesn't: the 8KB size limit (MAX_ADVERTISED_SCHEMA_BYTES = 8 * 1024) is more appropriate than #1352's 64KB. These schemas get serialized into every LLM call alongside all other tools, so a tighter budget is better for context management. We've asked #1352 to adopt the 8KB limit.

I'd recommend closing this PR in favor of #1352 to avoid the conflict. Thank you for the work — it clearly identified the right fix.

Minor note: the branch name fix/brave-search doesn't match the PR content, and there's an unrelated channels-src/whatsapp/Cargo.lock version bump included.

Copilot

Pull request overview

Fixes WASM tool schema advertisement so the LLM sees exported typed schemas for small/reasonable-size components (instead of always {}), while retaining the permissive advertisement + tool_info discovery path for large schemas. Also updates WASM loader warnings to reflect that WASM-exported metadata/schema can be used when sidecar fields are missing.

Changes:

Advertise small typed WASM-exported schemas directly; keep permissive fallback for large schemas.
Update/extend unit tests to cover small-vs-large exported schema advertisement behavior.
Adjust WASM loader warning messages about missing description / parameters in capabilities sidecars.

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 3 comments.

File	Description
src/tools/wasm/wrapper.rs	Adds size/typed checks to decide whether to advertise exported schemas; updates tests for small vs large exported schemas.
src/tools/wasm/loader.rs	Updates warning text for missing capabilities fields to indicate WASM-exported metadata/schema usage.
channels-src/whatsapp/Cargo.lock	Bumps the `whatsapp-channel` package version in the lockfile (aligned with `Cargo.toml`).

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+    fn should_advertise_discovery(schema: &serde_json::Value) -> bool {
+        Self::typed_property_count(schema) > 0
+            && schema.to_string().len() <= Self::MAX_ADVERTISED_SCHEMA_BYTES
+    }
+
    fn new(discovery: serde_json::Value) -> Self {
+        let advertised = if Self::should_advertise_discovery(&discovery) {
+            discovery.clone()
+        } else {
+            Self::permissive_schema()
+        };


+        Self::typed_property_count(schema) > 0
+            && schema.to_string().len() <= Self::MAX_ADVERTISED_SCHEMA_BYTES


                            path = %cap_path.display(),
                            "Capabilities file missing \"parameters\" field; \
-                             tool will accept any JSON object (permissive fallback)"
+                             using exported WASM schema when available"


fix: brave web search

83675c9

hanakannzashi requested a review from think-in-universe March 18, 2026 05:56

github-actions Bot added size: M 50-199 changed lines scope: tool/wasm WASM tool sandbox risk: medium Business logic, config, or moderate-risk modules and removed size: M 50-199 changed lines labels Mar 18, 2026

github-actions Bot added the contributor: new First-time contributor label Mar 18, 2026

gemini-code-assist Bot reviewed Mar 18, 2026

View reviewed changes

Comment thread src/tools/wasm/wrapper.rs

hanakannzashi changed the title ~~fix: brave web search~~ fix: WASM tool schema advertisement for exported typed schemas Mar 18, 2026

Rename WASM schema test for direct advertising behavior

ab806ef

github-actions Bot added the size: M 50-199 changed lines label Mar 18, 2026

henrypark133 reviewed Mar 18, 2026

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henrypark133 mentioned this pull request Mar 18, 2026

fix(wasm): advertise typed schemas by default #1352

Closed

henrypark133 requested a review from Copilot March 18, 2026 21:31

Copilot AI reviewed Mar 18, 2026

View reviewed changes

hanakannzashi closed this Mar 19, 2026

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fix: WASM tool schema advertisement for exported typed schemas - #1348

fix: WASM tool schema advertisement for exported typed schemas#1348
hanakannzashi wants to merge 2 commits into
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fix/brave-search

hanakannzashi commented Mar 18, 2026 •

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		Self::typed_property_count(schema) > 0
		&& schema.to_string().len() <= Self::MAX_ADVERTISED_SCHEMA_BYTES

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hanakannzashi commented Mar 18, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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Summary

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gemini-code-assist Bot commented Mar 18, 2026

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hanakannzashi commented Mar 18, 2026

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Review: WASM tool schema advertisement — overlaps with #1352

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hanakannzashi commented Mar 18, 2026 •

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