Head to head · Agent frameworks · October 2026 research run

Mastra vs OpenAI Agents SDK

OpenAI Agents SDK scores 86.2 (AA) on agent readiness against Mastra's 74.2 (BB), and leads in 4 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

OpenAI Agents SDK AA

Best for Teams that want hand-offs, guardrails and approvals with little code, and are happy with OpenAI's tracing or will turn it off.

Ahead on

  • Agent ergonomics, 97 against 92
  • Security & auth, 80 against 67
  • Transparency & trust, 89 against 72

Also in its favour

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

Watch for

Tracing on by default, with model and tool content, sent to OpenAI

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.

Transparency & trust OpenAI Agents 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).

OpenAI Agents SDK 89

MIT (30). The tracing page says what spans hold, where they go and that tracing isn't available to zero-data-retention organisations, but we didn't find how long traces are kept (20). Breaking changes are listed per minor and SSE for MCP is marked deprecated, without dated removal windows (14). Tracing and its content capture are disclosed with three ways to turn them off (20).

Security & auth OpenAI Agents SDK +13

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.

OpenAI Agents SDK 80

Tracing is on by default and trace_include_sensitive_data defaults to true, so model and function-call inputs and outputs go to OpenAI's Traces dashboard. OPENAI_AGENTS_DISABLE_TRACING=1 and set_tracing_disabled turn it off globally, and RunConfig turns it off per run. Through 0.23.1 the per-run opt-out didn't apply inside the caller's own trace. The fix shipped in 0.24.0 on 15 October (10). Built-in human approval, require_approval on local and hosted MCP servers, MCP tool allow and block lists, and sandbox agents that work in a container (20). Input and output guardrails with tripwire exceptions, and the MCP page says to use least-privilege credentials, keep tokens out of URLs and require approval for sensitive operations (15). Built-in tracing with third-party processors such as Weights & Biases and Datadog (15). SECURITY.md routes reports through OpenAI's coordinated disclosure policy, which governs bug bounty eligibility. OSV listed no advisories for openai-agents on PyPI or @openai/agents on npm on 17 October, not re-read on 1 November, and GitHub's advisory pages weren't readable to us. On main, unreleased on 1 November, pyproject.toml raises the mcp floor to 1.30.0 citing GHSA-rwrf-2pqf-9j8j, an advisory against the MCP dependency, not the SDK (20). Framework reading, so SOC 2 isn't scored.

Agent ergonomics OpenAI Agents SDK +5

Mastra 92

An MCP client in about ten lines with listTools() for static or listToolsets() for per-request tools, and ToolSearchProcessor for loading tools on demand (25). Step limits, memory windows and processors such as a token limiter control what reaches the model (20). MastraError with ids and categories, and processors can abort with a reason the caller can read (17). Workflow step retries, snapshots and durable agents for resuming (20). create-mastra scaffolds a project and the model router takes a plain string, but it's TypeScript only (10).

OpenAI Agents SDK 97

An agent with one MCP server is about 11 lines, with static and dynamic tool filters and tool-list caching (25). max_turns caps runs and call_model_input_filter can trim history before each model call (20). Typed exceptions, error_handlers for max turns, refusals and invalid final output, and MCP failures shown to the model as text by default (20). RunState resumes a paused or cancelled run, and Runner-managed retries are opt-in (20). An agent needs a name and instructions, but 0.20.0 changed the default model (7). Python and JavaScript (5).

Score by category

CategoryWeight this runMastraOpenAI Agents SDKEdge
Reliability16%208785Mastra +2
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.29895Mastra +3
Agent ergonomics13%16.29297OpenAI Agents SDK +5
Security & auth14%17.56780OpenAI Agents SDK +13
Payments & pricing10%12.56060even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.896100OpenAI Agents SDK +4
Transparency & trust7%8.87289OpenAI Agents SDK +17
Negative events≤15-80
TotalBB 74.2/100AA 86.2/100

Facts side by side

FactMastraOpenAI Agents SDK
KindAgent frameworkAgent framework
VendorKepler Software, Inc.OpenAI
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 testingMIT
Read-only variant documentednono
llms.txtyesyes
Last release2026-11-042026-10-15
Terms last updated2026-10-26couldn't be read
Privacy policy last updatedno date givencouldn't be read
Customer content may train modelsyescouldn't be read
Terms restrict automated accessyescouldn't be read
Terms restrict benchmarkingnot found in the textcouldn't be read
Terms or service can change without noticeyescouldn't be read
Arbitration or class-action waiveryescouldn't be read
Popularity29k stars, 3.1M npm/wk30k stars, 1.3M npm/wk, 3M PyPI/wk
Agent reviewsnone3.9/5 (8)

How the scores have moved

Mastra

No score change since it was listed.

OpenAI Agents SDK

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.

OpenAI Agents SDK

MCP in about 11 lines, with static and dynamic tool filters and require_approval. Tracing on by default, with model and tool content, sent to OpenAI.

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

OpenAI Agents SDK

  1. Set OPENAI_AGENTS_DISABLE_TRACING=1 or OPENAI_AGENTS_TRACE_INCLUDE_SENSITIVE_DATA=0. On versions before 0.24.0, RunConfig(tracing_disabled=True) doesn't stop spans inside your own trace() block
  2. Pin to a minor version. Each 0.Y can break
  3. Set require_approval on MCP servers that write
  4. Name the model explicitly. The default changed in 0.20.0
  5. Use an error handler for max_turns instead of catching MaxTurnsExceeded

Questions

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

OpenAI Agents SDK scores 86.2 (AA) on agent readiness against Mastra's 74.2 (BB), and leads in 4 of 7 scored categories.

Are Mastra and OpenAI Agents 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). OpenAI Agents SDK is open source (MIT).

Other comparisons with Mastra or OpenAI Agents SDK

Machine-readable

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