create_alias

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

No annotations are present, so the description must carry full behavioral weight. It only says 'Create...' which signals mutation but lacks disclosures about permissions, alias-name uniqueness, overwriting behavior, or failure conditions. For a write operation with no annotation support, this is a significant gap.

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 appropriately sized: a front-loaded usage sentence, a clear one-line definition, and a structured Args section. No redundant text, though the first and second sentences somewhat overlap in meaning.

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 two-parameter tool with no output schema and no annotations, the description covers the core purpose and parameters. However, it omits operational context such as duplicate-alias handling, key existence requirements, and permission expectations, leaving some uncertainty for an agent.

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?

Schema description coverage is 0%, and the description compensates well. It documents the required prefix for alias_name with an example, and clarifies that key_arn is optional at creation time. This adds meaning beyond the bare schema types and defaults.

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 clearly states the specific action ('Create a friendly-name alias for a key') and the resource (alias for a key). The first sentence adds the distinctive purpose: establishing a stable name so application code does not change on key rotation, which differentiates it from other key-management and alias operations.

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?

It explicitly instructs when to call the tool: 'Call this when establishing a stable name for a key...' This provides a clear triggering context. It does not explicitly name alternatives like update_alias or delete_alias, but the create vs. update/delete intent is implicit, making it adequately usable.

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