list-environments

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

With no annotations, the description carries the full burden. It discloses the return value ('CallToolResult with list of environment names') and the regional scope, but omits explicit statements about read-only behavior, pagination, or error handling. The phrase 'List all' implies a read operation, but it is not explicitly stated, leaving some behavioral ambiguity.

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 front-loaded with a clear purpose and uses headers for Args/Returns, making it structurally navigable. However, it is somewhat redundant: the first sentence already states the return, and the Args block duplicates information fully covered by the schema with less detail. The IMPORTANT note is useful but could be integrated more tightly.

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 simple list tool with no output schema, the description covers the essential aspects: what it lists, the region scope, the return type, and the alternative for detailed info. It lacks any mention of pagination or error behavior, but these are less critical for an environment-name listing, making it adequately complete rather than fully complete.

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 100%, so the baseline is 3. The description merely restates the parameters as 'region override' and 'profile name override' without adding any semantic detail beyond the schema's explicit defaults and fallback behaviors. No additional value is provided.

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 opens with 'List all MWAA environments in the specified region,' a specific verb and resource that clearly states the tool's purpose. It further clarifies the return is 'a list of environment names available in your AWS account for the given region,' and explicitly distinguishes itself from get-environment by directing users there for detailed info.

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?

Explicit guidance is provided: 'Use get-environment to retrieve detailed information about a specific environment' names the alternative and when to use it. Additionally, 'IMPORTANT: Use this tool instead of ‘aws mwaa list-environments’ CLI command' gives a direct usage directive for MCP agents that might consider the CLI fallback.

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