AWS bedrock-agentcore documentation change

Service: bedrock-agentcore · 2026-06-07 · Documentation low

File: bedrock-agentcore/latest/devguide/harness-environment.md

Summary

Expanded skill configuration options to allow fetching skills directly from S3/Git at invocation time, added authentication for private Git repos, and specified security requirements

Security assessment

Adds documentation about security controls for external skill sources: S3 permissions requirements (s3:GetObject, s3:ListBucket), Git authentication using credential providers, and execution role requirements. No evidence of addressing an existing vulnerability.

Diff

diff --git a/bedrock-agentcore/latest/devguide/harness-environment.md b/bedrock-agentcore/latest/devguide/harness-environment.md
index 46e693aad..2876a67dc 100644
--- a//bedrock-agentcore/latest/devguide/harness-environment.md
+++ b//bedrock-agentcore/latest/devguide/harness-environment.md
@@ -147 +147,49 @@ AWS CLI/boto3
-[Agent Skills](https://strandsagents.com/docs/user-guide/concepts/plugins/skills/) are bundles of markdown and scripts that give the agent domain knowledge on demand (e.g. how to work with Excel files, how to use a specific API). Skills must be present in the harness environment (the container filesystem) before they can be used. The `skills` parameter on the harness or at invoke time is a **pointer** to a path inside the environment - it does not upload or install the skill.
+[Agent Skills](https://strandsagents.com/docs/user-guide/concepts/plugins/skills/) are bundles of markdown and scripts that give the agent domain knowledge on demand (e.g. how to work with Excel files, how to use a specific API). Each entry in the `skills` list is either a `path` to a skill already in the harness environment, or an `s3` or `git` source that the harness fetches for you at invocation time. You can set `skills` as a default on the harness, or override it per invocation.
+
+### Fetch a skill from S3 or Git
+
+Instead of placing a skill in the environment yourself, point the harness at a skill stored in Amazon S3 or a Git repository and the harness fetches it for you - no image rebuild and no session setup required.
+
+  * **Amazon S3** \- set `s3.uri` to the skill directory (for example, `s3://my-skills-bucket/skills/company-style/`). The harness downloads it with the execution role, which needs `s3:GetObject` and `s3:ListBucket` on the bucket (see [Security and access controls](./harness-security.html)).
+
+  * **Git over HTTPS** \- set `git.url` to the repository URL, and `git.path` to pull a single skill from a subdirectory. For a private repository, set `git.auth.credentialArn` to an [AgentCore Identity](https://docs.aws.amazon.com/bedrock-agentcore/latest/devguide/identity.html) credential provider holding a personal access token (`git.auth.username` is optional, default `oauth2`).
+
+
+
+
+###### Example
+
+boto3
+    
+
+Attach a skill from S3 and a skill from a public Git repository for a single invocation:
+    
+    
+    response = client.invoke_harness(
+        harnessArn=HARNESS_ARN,
+        runtimeSessionId=SESSION_ID,
+        skills=[
+            {"s3": {"uri": "s3://my-skills-bucket/skills/company-style/"}},
+            {"git": {"url": "https://github.com/anthropics/skills", "path": "skills/docx"}},
+        ],
+        messages=[{"role": "user", "content": [{"text": "Draft a one-paragraph summary of this report."}]}],
+    )
+
+To fetch a skill from a private Git repository, add `auth` with the ARN of a credential provider that holds a personal access token:
+    
+    
+    skills=[
+        {
+            "git": {
+                "url": "https://github.com/my-org/internal-skills",
+                "path": "excel",
+                "auth": {
+                    "credentialArn": "arn:aws:bedrock-agentcore:us-west-2:123456789012:token-vault/default/apikeycredentialprovider/my-github-pat"
+                },
+            }
+        }
+    ]
+
+The harness fetches each skill on the first invocation of a session and re-fetches it when a new session starts, so the agent always gets the current version. Each source must contain a `SKILL.md`, an S3 skill must be 1 GB or smaller, and a Git fetch must complete within 60 seconds; otherwise the invocation fails with a descriptive error.
+
+S3 sources need no internet access; Git (HTTPS) sources require internet egress, the same as pulling a custom container image or reaching a remote MCP server.