AWS MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, and the description carries minimal behavioral context. While 'List' implies read-only, there's no disclosure of pagination behavior, rate limiting, what shard attributes are returned, or that this is a safe non-destructive operation.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with no redundant words. However, it borders on under-specification given the lack of annotations and output schema; one additional sentence covering behavioral traits would improve completeness without sacrificing clarity.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 3-parameter read-only tool with complete schema coverage, the description is minimally viable. However, given no annotations, no output schema, and potential confusion with sibling Kinesis tools, it lacks contextual guidance on expected return values and operational prerequisites.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 100% schema description coverage, the schema fully documents all three parameters (profile, region, stream_name) with examples and formats. The description adds no semantic information beyond the schema, warranting the baseline score of 3.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('List') and resource ('shards in a Kinesis stream'), making the purpose immediately clear. However, it fails to distinguish from the sibling tool aws_kinesis_describe_stream, which also returns shard information but with different semantics and output format.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance provided on when to use this tool versus aws_kinesis_describe_stream or aws_kinesis_list_streams. No mention of prerequisites (e.g., stream must exist) or that this is typically used to obtain shard IDs for subsequent read/write operations.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.