chore(epic/1.0_breaking_changes): release 1.0.0-beta.0 (#479)

🤖 I have created a release *beep* *boop*
---


##
[1.0.0-beta.0](v1.0.0-alpha.0...v1.0.0-beta.0)
(2026-07-01)

The v0.3 backward-compatibility layer is now complete, marking this
release as the first one bringing v1.0 and v0.3 support together.
Backward compatibility with v0.3 was implemented across all three
transports (JSON-RPC, REST, gRPC), agent-card resolution, and push
notifications — closing
[#452](#452).
A v1.0 server can transparently accept v0.3 clients (and a v1.0 client
can talk to v0.3 servers) by opting in with `legacyCompat: { enabled:
true }` on the relevant transport.

See the [v0.3 → v1.0 migration
guide](https://github.com/a2aproject/a2a-js/blob/v1.0.0-beta.0/docs/migration-guide.md)
and the [end-user v0.3 compatibility
guide](https://github.com/a2aproject/a2a-js/blob/v1.0.0-beta.0/docs/compatibility-v0_3.md).


### Features

* add compat-v1 client and server samples to demonstrate A2A v0.3
backward compatibility
([#520](#520))
([fce0b3f](fce0b3f))
* add opt-in legacy v0.3 compatibility to JSON-RPC handler and improve
extension header support
([#501](#501))
([f707350](f707350))
* add v0.3 compatibility layer for client and server agent-card handling
([#504](#504))
([75685f2](75685f2))
* add v0.3 gRPC compat layer
([#505](#505))
([314d9e3](314d9e3))
* default to v0.3 if version not provided
([#511](#511))
([ad7f772](ad7f772))
* defined compat-specific consts and mappings
([#478](#478))
([db0c595](db0c595))
* implement legacy v0.3 JSON-RPC transport handler
([#493](#493))
([d191d91](d191d91))
* implement legacy v0.3 REST support with compatible transport handler
and middleware routing
([#495](#495))
([da9a968](da9a968))
* implement v0.3 ITK cross-SDK validation workflows
([#513](#513))
([c9385f3](c9385f3))
* implement v0.3 JSON-RPC client transport
([#499](#499))
([46aa5d6](46aa5d6))
* implement v0.3 protocol compatibility for RestTransportFactory
([#503](#503))
([b172482](b172482))
* implement versioned push notification serializers with legacy v0.3
compatibility support
([#507](#507))
([0261be8](0261be8))
* normalize extension headers based on negotiated protocol version
([#510](#510))
([74a51ee](74a51ee))
* replace automatic v0.3 agent card synthesis with explicit
per-interface advertisement
([#560](#560))
([60ad3b2](60ad3b2))


### Bug Fixes

* **compat:** wrap primitive Part.data values instead of throwing
([#537](#537))
([7647db5](7647db5))
* **server/rest:** handle undefined historyLength to return full task
history ([#527](#527))
([fa9ebce](fa9ebce)),
closes [#535](#535)
* **server:** handle AUTH_REQUIRED lifecycle per spec
([#523](#523))
([68826c2](68826c2))
* **server:** make cancelTask idempotent on the canceled state
([#545](#545))
([1d17a78](1d17a78))
* **server:** make push notification config id optional with server-side
UUID ([#543](#543))
([83af8c3](83af8c3))
* **server:** merge Task history in ResultManager instead of overwriting
([#524](#524))
([4e1d4f7](4e1d4f7)),
closes [#532](#532)
* **server:** preserve activated extensions in response header
([#544](#544))
([26184b4](26184b4))
* **server:** propagate return to SSE generators to prevent listener
leaks ([#526](#526))
([a690734](a690734)),
closes [#534](#534)
* **server:** synthesize correct error Task id in blocking and streaming
paths ([#525](#525))
([a3dd703](a3dd703)),
closes [#533](#533)
* **server:** yield Task snapshot on resubscribe when bus is inactive
([#542](#542))
([cd8f8fc](cd8f8fc))

---
This PR was generated with [Release
Please](https://github.com/googleapis/release-please). See
[documentation](https://github.com/googleapis/release-please#release-please).

---------

Co-authored-by: JakubWorek <worekkuba@gmail.com>

Author: a2a-bot

.release-please-manifest.json

@@ -1,3 +1,3 @@
 {
-  ".": "1.0.0-alpha.0"
+  ".": "1.0.0-beta.0"
 }

CHANGELOG.md

@@ -1,5 +1,46 @@
 # Changelog
 
+## [1.0.0-beta.0](https://github.com/a2aproject/a2a-js/compare/v1.0.0-alpha.0...v1.0.0-beta.0) (2026-07-01)
+
+The v0.3 backward-compatibility layer is now complete, marking this release as the first one bringing v1.0 and v0.3 support together.
+Backward compatibility with v0.3 was implemented across all three transports (JSON-RPC, REST, gRPC), agent-card resolution, and push notifications — closing [#452](https://github.com/a2aproject/a2a-js/issues/452).
+A v1.0 server can transparently accept v0.3 clients (and a v1.0 client can talk to v0.3 servers) by opting in with `legacyCompat: { enabled: true }` on the relevant transport.
+
+See the [v0.3 → v1.0 migration guide](https://github.com/a2aproject/a2a-js/blob/v1.0.0-beta.0/docs/migration-guide.md)
+and the [end-user v0.3 compatibility guide](https://github.com/a2aproject/a2a-js/blob/v1.0.0-beta.0/docs/compatibility-v0_3.md).
+
+
+### Features
+
+* add compat-v1 client and server samples to demonstrate A2A v0.3 backward compatibility ([#520](https://github.com/a2aproject/a2a-js/issues/520)) ([fce0b3f](https://github.com/a2aproject/a2a-js/commit/fce0b3f8d89e80b1ad006bfb799e262e991977e9))
+* add opt-in legacy v0.3 compatibility to JSON-RPC handler and improve extension header support ([#501](https://github.com/a2aproject/a2a-js/issues/501)) ([f707350](https://github.com/a2aproject/a2a-js/commit/f70735090a6e27bbc0313c6b4d710f26a92e7b39))
+* add v0.3 compatibility layer for client and server agent-card handling ([#504](https://github.com/a2aproject/a2a-js/issues/504)) ([75685f2](https://github.com/a2aproject/a2a-js/commit/75685f2ce0a3c3ba970c000cf0935d9df3b0bbcb))
+* add v0.3 gRPC compat layer ([#505](https://github.com/a2aproject/a2a-js/issues/505)) ([314d9e3](https://github.com/a2aproject/a2a-js/commit/314d9e36946d52c3c20c8f55fac77a2a715fb4fb))
+* default to v0.3 if version not provided ([#511](https://github.com/a2aproject/a2a-js/issues/511)) ([ad7f772](https://github.com/a2aproject/a2a-js/commit/ad7f772308472c770d0ef65a23f939966741eb82))
+* defined compat-specific consts and mappings ([#478](https://github.com/a2aproject/a2a-js/issues/478)) ([db0c595](https://github.com/a2aproject/a2a-js/commit/db0c595581e833be86fe20d9e84b22ec6a5296e3))
+* implement legacy v0.3 JSON-RPC transport handler ([#493](https://github.com/a2aproject/a2a-js/issues/493)) ([d191d91](https://github.com/a2aproject/a2a-js/commit/d191d911479380a0fa0eca9ca4a2975d530143e6))
+* implement legacy v0.3 REST support with compatible transport handler and middleware routing ([#495](https://github.com/a2aproject/a2a-js/issues/495)) ([da9a968](https://github.com/a2aproject/a2a-js/commit/da9a9682a34e73578ebed75813afa2fd4e15d241))
+* implement v0.3 ITK cross-SDK validation workflows ([#513](https://github.com/a2aproject/a2a-js/issues/513)) ([c9385f3](https://github.com/a2aproject/a2a-js/commit/c9385f338863000a158ac030614e1821a3355ccb))
+* implement v0.3 JSON-RPC client transport ([#499](https://github.com/a2aproject/a2a-js/issues/499)) ([46aa5d6](https://github.com/a2aproject/a2a-js/commit/46aa5d6fe984f01c3d078342eefcd0f6af6eb9d4))
+* implement v0.3 protocol compatibility for RestTransportFactory ([#503](https://github.com/a2aproject/a2a-js/issues/503)) ([b172482](https://github.com/a2aproject/a2a-js/commit/b172482821c41ed88d85698e02b49754100170cf))
+* implement versioned push notification serializers with legacy v0.3 compatibility support ([#507](https://github.com/a2aproject/a2a-js/issues/507)) ([0261be8](https://github.com/a2aproject/a2a-js/commit/0261be8585714ba9804a6ad8cb3eb4578404c21c))
+* normalize extension headers based on negotiated protocol version ([#510](https://github.com/a2aproject/a2a-js/issues/510)) ([74a51ee](https://github.com/a2aproject/a2a-js/commit/74a51eee0b7cc0c708bbca4799a777f1d47530a9))
+* replace automatic v0.3 agent card synthesis with explicit per-interface advertisement ([#560](https://github.com/a2aproject/a2a-js/issues/560)) ([60ad3b2](https://github.com/a2aproject/a2a-js/commit/60ad3b2b6aa1cce70a372dcf5c63ac46a1059544))
+
+
+### Bug Fixes
+
+* **compat:** wrap primitive Part.data values instead of throwing ([#537](https://github.com/a2aproject/a2a-js/issues/537)) ([7647db5](https://github.com/a2aproject/a2a-js/commit/7647db51720b7f64a6df86d829627c207debaf3b))
+* **server/rest:** handle undefined historyLength to return full task history ([#527](https://github.com/a2aproject/a2a-js/issues/527)) ([fa9ebce](https://github.com/a2aproject/a2a-js/commit/fa9ebcef97ddf2bbedb4fbe42822cde8b145b66e)), closes [#535](https://github.com/a2aproject/a2a-js/issues/535)
+* **server:** handle AUTH_REQUIRED lifecycle per spec ([#523](https://github.com/a2aproject/a2a-js/issues/523)) ([68826c2](https://github.com/a2aproject/a2a-js/commit/68826c251a4bc789cbbdf2904c66eeb61cbb3715))
+* **server:** make cancelTask idempotent on the canceled state ([#545](https://github.com/a2aproject/a2a-js/issues/545)) ([1d17a78](https://github.com/a2aproject/a2a-js/commit/1d17a78d8c42b84fdf84c8e6a6a7c99b794e6b63))
+* **server:** make push notification config id optional with server-side UUID ([#543](https://github.com/a2aproject/a2a-js/issues/543)) ([83af8c3](https://github.com/a2aproject/a2a-js/commit/83af8c37eaffd6200721bc73beae85993567d41d))
+* **server:** merge Task history in ResultManager instead of overwriting ([#524](https://github.com/a2aproject/a2a-js/issues/524)) ([4e1d4f7](https://github.com/a2aproject/a2a-js/commit/4e1d4f75d0d468776a31e44b378013f098ccaf78)), closes [#532](https://github.com/a2aproject/a2a-js/issues/532)
+* **server:** preserve activated extensions in response header ([#544](https://github.com/a2aproject/a2a-js/issues/544)) ([26184b4](https://github.com/a2aproject/a2a-js/commit/26184b4aec53106a4d5c73a6ed76f1a46bf1ecba))
+* **server:** propagate return to SSE generators to prevent listener leaks ([#526](https://github.com/a2aproject/a2a-js/issues/526)) ([a690734](https://github.com/a2aproject/a2a-js/commit/a6907348c3160331e37985c181bd9fff968d10b6)), closes [#534](https://github.com/a2aproject/a2a-js/issues/534)
+* **server:** synthesize correct error Task id in blocking and streaming paths ([#525](https://github.com/a2aproject/a2a-js/issues/525)) ([a3dd703](https://github.com/a2aproject/a2a-js/commit/a3dd703ecc94c724e46e74097c2bb1bc2655bc8e)), closes [#533](https://github.com/a2aproject/a2a-js/issues/533)
+* **server:** yield Task snapshot on resubscribe when bus is inactive ([#542](https://github.com/a2aproject/a2a-js/issues/542)) ([cd8f8fc](https://github.com/a2aproject/a2a-js/commit/cd8f8fc75b9d73cbeac07969c38d2d41bf9eb881))
+
 ## 1.0.0-alpha.0 (2026-05-11)
 
 See the [v0.3 -> v1.0-alpha.0 migration guide](https://github.com/a2aproject/a2a-js/blob/v1.0.0-alpha.0/docs/migration-guide.md).