Agent Development Kit (ADK) vs Strands Agents

Agent Development Kit (ADK) 87

An API reference on adk.dev (25). llms.txt with about 250 entries and Markdown versions of each page (10). The docs explain the agent types and when to use workflow agents, but say little about when not to use ADK (15). Tools are typed functions, and McpToolset keeps the server's schemas (12). Examples throughout, but the MCP page has no error handling section and we found no exception reference (10). Dated changelog and release notes (15).

Strands Agents 95

Framework reading. Typed Python and TypeScript APIs with a reference for each (25). llms.txt with a Markdown twin of every page (10). The llms.txt and docs say when to use Strands over a hand-written loop and when to take the harness rather than the SDK (18). Tools are typed from decorated functions or Zod schemas (15). Python and TypeScript examples on every page, stop reasons and hook events documented, with no catalogue of exceptions (12). Versioning page and tagged releases per package (15). 25+10+18+15+12+15 = 95.

Agent Development Kit (ADK) 80

Official packages on PyPI (Requires-Python >=3.11 since 2.12.0, constraint files for 3.11 to 3.15) and npm (20). The continuous-integration workflow passes on main, per the 1 October check, not re-read on 1 November (25). 300 open issues and 261 open pull requests, per the 1 October check, not re-read on 1 November (12). The changelog calls out breaking changes, but they keep shipping in minor releases of a post-1.0 package (2.6.0 on 2026-07-29 and 2.7.0 on 2026-08-13), 2.12.0 on 2026-10-13 dropped Python 3.10 with no line in its changelog, and 2.8.0 reverted an A2A guard that had broken every tool confirmation. On 8 October the changelog relabelled the 2.11.0 dev UI config change a bug fix and the 2.9.0 resumption changes behaviour changes. 2.13.0 (22 October) marks one more breaking change, the telemetry schema default, in a minor release (8). 2.12.0, past 1.0 (15).

Strands Agents 87

Local-package reading. Official PyPI and npm packages with Python 3.10 and Node 22 stated (20). A public CI workflow runs lint, type checks, unit and integration tests for each package on pull requests to main, plus security-audit workflows, and the latest Python, TypeScript, harness and MCP runs on main passed on 6 November (25). 664 open issues and 1,151 open issues and pull requests on 6 November, with 545 issues opened in the 90 days to 3 November. Of the 50 newest, 12 had a comment and 15 were closed, and 9 of the 40 newest open items carry a bug label. An issue-responder workflow runs on new issues (12). A written semantic versioning policy, experimental APIs kept apart, and deprecations removed only at a major (15). 1.0 since 15 July 2025 (15). 20+25+12+15+15 = 87.

Agent Development Kit (ADK) 80

An agent with one MCP server is about 15 lines with the built-in McpToolset, and tool_filter limits which tools load, with no dynamic filtering or deferred loading that we saw (20). RunConfig caps model calls per run, and the context compression page documents token-based and sliding-window compaction through EventsCompactionConfig, plus context caching (20). No exception reference or MCP error handling documented (5). Invocations are resumable, model calls take retry options, and 2.11.0 adds an abort_signal for graceful cancellation (20). An agent needs a name, a model and an instruction, in Python, TypeScript, Go, Java or Kotlin (15).

Strands Agents 87

Framework reading. An MCPClient is passed straight to the agent in a few lines and its lifecycle is managed, with tool filtering per client (22). Conversation managers, turn limits, token budgets and cancellation bound each run (20). Stop reasons and typed events, and hooks that can retry a model or tool call (16). Retry strategies, session managers that persist and resume a conversation, and interrupts that resume where they paused (17). Two official languages, but the default provider is Bedrock, which needs AWS credentials and model access (12). 22+20+16+17+12 = 87.