build(deps): bump @mastra/core from 1.52.1 to 1.57.0

[dependabot]

Bumps @mastra/core from 1.52.1 to 1.57.0.

Release notes

Sourced from @​mastra/core's releases.

August 5, 2026

Highlights

Tool Result Guardrails via processToolResult

A new processToolResult processor lifecycle hook runs after each tool execution and before results enter message history, enabling prompt-injection/sensitive-data scanning, transformation, or aborting the run before the LLM sees tool output.

Transient Agent Signals (Per-turn Context Without Persistence)

Signals now support transient: true end-to-end (@mastra/core, @mastra/server, @mastra/memory, and typed support in @mastra/client-js) so you can deliver “reminder” context to the current model call without retaining it in stored conversation/observational memory.

New Observability Exporter: @mastra/deepeval

Introduces @mastra/deepeval, an exporter that sends Mastra traces to Confident AI (DeepEval) for evaluation and monitoring, mapping Mastra spans into Confident’s agent/LLM/tool/retriever/custom types with tokens, tool calls, and metrics.

Better Tooling Visibility in Traces + PostHog LLM Analytics

Model generations now capture full tool definitions (name/description/JSON schema) as a tools attribute on MODEL_GENERATION spans, and @mastra/posthog forwards these as $ai_tools so analytics can show exactly which tool schemas each generation ran with.

Much Faster Mastra Platform Sandbox Exec (Private Network Direct Dial)

@mastra/platform-workspace can now execute commands directly over Railway’s private network when available (dropping exec latency from ~400ms p50 to ~16ms p50), accelerating all sandbox filesystem operations and adding pluggable SandboxAddressRegistry support.

Breaking Changes

• None noted in this changelog.

Changelog

@​mastra/core@1.57.0

Minor Changes

• Added transient to non-state agent signals. Set transient: true when a processor should deliver a reminder to the current model call without retaining it in conversation history. (#18909)

  await sendSignal?.({
    type: 'reactive',
    contents: 'Stay on the current task.',
    transient: true,
  });

• Added tool definitions to MODEL_GENERATION span attributes. The tools made available to the model (name, description, and JSON-schema parameters) are now captured once per generation as the tools attribute, so observability exporters can surface which tool schemas the model ran with. Per-step tool names (after activeTools filtering) remain on MODEL_INFERENCE spans as availableTools. Related: #20242 (#20243)

  // Any exporter reading MODEL_GENERATION spans now receives:
  span.attributes.tools;
  // [
  //   {
  //     type: 'function',
  //     name: 'get_weather',
  //     description: 'Get the weather for a city',
  //     parameters: { type: 'object', properties: { city: { type: 'string' } }, required: ['city'] },
  //   },
  // ]

... (truncated)

Commits

• ca935ef chore: version - exit prerelease mode
• 8d2399b chore(deps): update ai sdk (#20149)
• f933ba3 fix(core): record provider-executed tool results when toolCallId differ (#157...
• fb561aa chore: regenerate providers and docs [skip ci]
• 9672fab feat(core): add transient option to agent signals (#18909)
• d8fa243 feat(core): add processToolResult processor lifecycle hook (#16012)
• d8d259c chore: version packages (alpha) (#20717)
• c848e65 fix(core): exempt memory-sourced messages from the resourceId guard in inputT...
• 8d1aeb8 fix(aiv5-adapter): pass through OpenAI Files API file IDs without corrupting ...
• e932ad2 docs: add Neon as built-in gateway (#20573)
• Additional commits viewable in compare view

[github-actions]

Coverage Report for server

Status	Category	Percentage	Covered / Total
🟢	Lines	98.38% (🎯 97%)	3173 / 3225
🟢	Statements	97.7% (🎯 96%)	3322 / 3400
🟢	Functions	98.74% (🎯 97%)	551 / 558
🟢	Branches	89.1% (🎯 87%)	1300 / 1459

File Coverage

No changed files found.

Generated in workflow #1869 for commit 7ea0d5e by the Vitest Coverage Report Action

[github-actions]

Coverage Report for web

Status	Category	Percentage	Covered / Total
🟢	Lines	97.31% (🎯 96%)	1524 / 1566
🟢	Statements	96.23% (🎯 95%)	1611 / 1674
🟢	Functions	95.82% (🎯 95%)	643 / 671
🟢	Branches	90.71% (🎯 88%)	1016 / 1120

File Coverage

No changed files found.

Generated in workflow #1869 for commit 7ea0d5e by the Vitest Coverage Report Action

[github-actions]

Coverage Report for shared

Status	Category	Percentage	Covered / Total
🟢	Lines	99.12% (🎯 98%)	226 / 228
🟢	Statements	81.2% (🎯 80%)	242 / 298
🟢	Functions	100% (🎯 98%)	76 / 76
🟢	Branches	63.52% (🎯 62%)	101 / 159

File Coverage

No changed files found.

Generated in workflow #1869 for commit 7ea0d5e by the Vitest Coverage Report Action

[github-actions]

Coverage Report for widget

Status	Category	Percentage	Covered / Total
🟢	Lines	100% (🎯 98%)	230 / 230
🟢	Statements	99.59% (🎯 96%)	247 / 248
🟢	Functions	100% (🎯 98%)	45 / 45
🟢	Branches	95.96% (🎯 92%)	119 / 124

File Coverage

No changed files found.

Generated in workflow #1869 for commit 7ea0d5e by the Vitest Coverage Report Action

[dependabot]

Dependabot can't parse your pnpm-lock.yaml. Because of this, Dependabot cannot update this pull request.

[dependabot]

Dependabot can't parse your pnpm-lock.yaml. Because of this, Dependabot cannot update this pull request.

[owk-owk130]

mastra 系 9 件（#1008 #1012 #1006 #1004 #999 #997 #995 #979 #1014）はまとめて保留にします。ローカル検証の結果、core 1.54 以降は Cloudflare Workers 向けのバンドルが通りません。

症状

wrangler deploy --dry-run が失敗する。

No matching export in "unicorn-magic/default.js" for import "toPath"
No matching export in "unicorn-magic/default.js" for import "traversePathUp"
  npm-run-path/index.js:4:8

core の src/workspace/sandbox/execa.ts は execa を「バンドラに解決させない」意図で動的 import にしているが、tsdown が出力時に import("execa") のリテラルへ畳んでしまい、esbuild が execa → npm-run-path → unicorn-magic を解決して落ちる。

上流の既知バグ: mastra-ai/mastra#20638（open）/ 修正 PR #20639（未マージ）

検証結果

core	結果
1.52.1（現行）	✅ バンドル成功
1.54.0	❌ execa/unicorn-magic
1.55.0	❌ execa/unicorn-magic
1.56.0	❌ execa/unicorn-magic
1.57.0	❌ execa/unicorn-magic

core を据え置いて衛星パッケージだけ上げる案も不可。peer 範囲は満たすのに実装が新しい core のシンボルを要求するため、バンドル時に未解決になる。

• @mastra/ai-sdk 1.8.0 → core の smoothStream を import（1.53.0 には無い）
• @mastra/libsql 1.19.0 / @mastra/cloudflare-d1 1.2.0 → core の validateStorageMetadataFilter を import（1.52.1 には無い）

つまり全部上げるか全部据え置くかの二択で、「全部上げる」がバンドル不能。上流 #20639 が入った core リリースを待ちます。

注意

lint / test は全て緑（1311 + 169 + 670 + 62 tests）だった。CI は lint と test だけで wrangler deploy を通していないため、この破壊は CI では検出できない。マージすると develop への push 時の dev デプロイで初めて落ちる。

[dependabot]

Superseded by #1028.