Head to head · Agent frameworks · October 2026 research run

Mastra vs AI SDK

AI SDK scores 89.8 (AA) on agent readiness against Mastra's 74.2 (BB), and leads in 6 of 7 scored categories. Both do agent frameworks.

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Which one, for what

Mastra BB

Best for TypeScript teams that want agents, workflows, memory, evals and a local Studio in one framework.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

Malicious versions of Mastra npm packages, including @mastra/core 1.42.1, were published on 17 June 2026

AI SDK AA

Best for TypeScript teams building agents and chat UIs who want one API across many providers and a short path to MCP.

Ahead on

  • Reliability, 93 against 87
  • Security & auth, 90 against 67
  • Transparency & trust, 89 against 72

Also in its favour

  • No incidents deducted, where Mastra loses 8 points for them

Watch for

TypeScript only, and ai 7.x needs Node 22 or newer

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Security & auth AI SDK +23

Mastra 67

The CLI sends PostHog analytics, server startup sends token counts per model and a count of registered agents, tools and MCP servers, and Studio sends browser analytics, all on by default and documented, with one opt-out, MASTRA_TELEMETRY_DISABLED=1. Since #26986 (16 October 2026) each server process also reports token use per provider and model every 15 minutes, and the telemetry reference read on 6 November says server events carry a project identifier that is a raw Platform UUID or a hash of the Git origin remote, so they "aren't anonymous" (12). requireToolApproval on agents and MCP servers, allowedHosts for MCP HTTP, a curated environment for stdio servers, and sandboxed workspaces (20). PromptInjectionDetector, PII and moderation processors, and docs that call tool results untrusted model input (15). Built-in tracing with OpenTelemetry and other exporters (15). No SECURITY.md, no security.txt and no bug bounty found. A blog post says Mastra is SOC 2 Type II audited, which isn't scored for a framework, and we found no public advisory from Mastra about the June incident (5). Framework reading. 15+20+15+15+5 = 70 on 6 October, 12+20+15+15+5 = 67 on 6 November.

AI SDK 90

No telemetry until an OpenTelemetry integration is registered. String model IDs route to Vercel's AI Gateway by default, which is documented and needs a Vercel key, so it isn't silent (25). Per-tool approval, HMAC-signed approvals against forged client history, and Open Policy Agent rules in @ai-sdk/policy-opa, though sandboxes are experimental (20). ToolLoopAgent rejects system messages in prompts by default as an injection risk, URL fetches are checked against private addresses, and MCP HTTP transport refuses redirects by default, but there's no guardrail primitive (10). OpenTelemetry spans for every model and tool call to any backend, opt-in (15). HackerOne programme, a valid security.txt, SECURITY.md and two low-severity advisories published with fixed versions (20). Framework reading, so SOC 2 isn't scored.

Transparency & trust AI SDK +17

Mastra 72

Apache 2.0 for the core, with ee/ directories source-available under the Mastra Enterprise License (25). The privacy policy (last published 25 April 2025) covers the website, the Teams plan states six months' retention, and the subprocessor list sits in a trust centre our reader couldn't render (15). Migration guides and deprecation warnings, without dated removal windows (12). Every telemetry stream is documented with links to its source and one opt-out, and the reference now spells out what the project identifiers can be correlated with (20).

AI SDK 89

Apache 2.0 (30). The library stores nothing. The AI Gateway's ZDR page says it doesn't retain prompts or outputs and per-request ZDR is available on Pro and Enterprise, and Vercel's privacy notice is dated 1 June 2026, but we didn't read a DPA or subprocessor list (22). Deprecated APIs are removed only at majors with a migration guide, and 6.x and 5.x keep getting releases, without a written support window (14). Telemetry is opt-in and documented, with switches for inputs and outputs (20).

Reliability AI SDK +6

Mastra 87

Official npm packages, Node 22.13 or newer (20). Public CI workflows for unit, store, workspace and e2e tests; on 6 November the newest runs on main (Version Packages, Trigger Cloud Integration Tests) succeeded, while the test workflows themselves run on pull requests (22). 436 open issues and 795 open issues and pull requests on 6 November from GitHub's API, with 2,077 issues opened in the 90 days to 3 November; all 50 newest had a comment and 24 were closed, with issue-triage automation (18). A changesets CHANGELOG per package, a CI gate that needs approval for any major bump and migration guides, but no written versioning policy found, and .network() is deprecated without a removal date (12). 1.82.0 (15). 20+22+18+12+15 = 87, up from 74 on 6 October, when GitHub couldn't be read.

AI SDK 93

Official npm packages, with ai 7.x requiring Node 22 or newer (20). A public CI workflow with lint, type checks, unit tests, Node-version tests, MCP tests on Windows and e2e tests runs on every push to main, and the newest completed CI runs on main passed on 6 November (25). 1,517 open issues and pull requests on 6 November from GitHub's API, with 1,059 issues opened in the 90 days to 3 November; 47 of the 50 newest had a comment and 32 were closed (18). A written versioning page with breaking changes only in majors, experimental_ prefixes for unstable APIs and a migration guide per major (15). 7.0.163 (15). 20+25+18+15+15 = 93, up from 73 on 6 October, when GitHub couldn't be read.

Score by category

CategoryWeight this runMastraAI SDKEdge
Reliability16%208793AI SDK +6
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.298100AI SDK +2
Agent ergonomics13%16.29295AI SDK +3
Security & auth14%17.56790AI SDK +23
Payments & pricing10%12.56060even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.89697AI SDK +1
Transparency & trust7%8.87289AI SDK +17
Negative events≤15-80
TotalBB 74.2/100AA 89.8/100

Facts side by side

FactMastraAI SDK
KindAgent frameworkAgent framework
VendorKepler Software, Inc.Vercel Inc.
Hosted endpointno (local only)no (local only)
Transports
AuthAPI keyAPI key
PricingFreeFree
x402nono
LicenceApache-2.0 for the core. Code under ee/ directories is source-available under the Mastra Enterprise License, free for development and testingApache-2.0
Read-only variant documentednono
llms.txtyesyes
Last release2026-11-042026-11-05
Terms last updated2026-10-262026-06-01
Privacy policy last updatedno date given2026-06-01
Customer content may train modelsyesyes, with an opt-out
Terms restrict automated accessyesnot found in the text
Terms restrict benchmarkingnot found in the textnot found in the text
Terms or service can change without noticeyesnot found in the text
Arbitration or class-action waiveryesyes
Popularity29k stars, 3.1M npm/wk28k stars, 44.9M npm/wk

Verdicts

Mastra

A TypeScript framework with agents, workflows with suspend and resume, memory, an MCP client and server, per-server tool approval and built-in guardrail processors including a prompt-injection detector. On 17 June 2026 malicious versions of its npm packages were published, and the CLI, server and Studio send usage analytics by default, with token counts every 15 minutes.

AI SDK

A TypeScript agent toolkit with ToolLoopAgent, a built-in MCP client, per-tool approvals that can be HMAC-signed, opt-in OpenTelemetry and durable runs through WorkflowAgent. It ships three major versions in 14 months (5.0, 6.0, 7.0), each with a migration guide, and plain string model IDs route through Vercel's AI Gateway unless another provider is set.

Before you call either

Mastra

  1. Set MASTRA_TELEMETRY_DISABLED=1 in every environment that runs the CLI, the server or Studio
  2. Pin exact versions with a lockfile, and make sure no 17 June 2026 release such as @mastra/core 1.42.1 is installed
  3. Set requireToolApproval on MCP servers that write, and allowedHosts when server URLs come from configuration
  4. Add PromptInjectionDetector as an input processor when tools return web or user content
  5. Use supervisor agents through generate() or stream(). .network() is deprecated

AI SDK

  1. Pass a provider instance such as openai('model') if traffic shouldn't go through Vercel's AI Gateway
  2. Set toolApproval on tools that write, and experimental_toolApprovalSecret when approvals come back from a browser
  3. Raise or replace the default stop condition of 20 steps with stopWhen
  4. Close the MCP client after the run, and use HTTP transport outside local development
  5. Set recordInputs and recordOutputs to false when spans would carry secrets

Questions

Which is better for AI agents, Mastra or AI SDK?

AI SDK scores 89.8 (AA) on agent readiness against Mastra's 74.2 (BB), and leads in 6 of 7 scored categories.

Are Mastra and AI SDK open source?

Yes. Mastra is open source (Apache-2.0 for the core. Code under ee/ directories is source-available under the Mastra Enterprise License, free for development and testing). AI SDK is open source (Apache-2.0).

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