List environments (v1 fallback)

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

Annotations already declare readOnlyHint=true and idempotentHint=true, and the description adds useful behavioral context: no permission gate and the return structure (id, name, agents[], urls[]). It does not mention potential pagination or rate limits, but for a no-parameter read-only list the added detail is sufficient.

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?

Three sentences, each earning its place: purpose, comparison, and return format. The description is front-loaded with the verb and resource, contains no filler, and all information is directly useful.

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, parameterless, read-only list tool with no output schema, the description fully covers purpose, usage, behavioral nuances, and return format. It is a complete and self-sufficient description for an agent to select and invoke correctly.

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?

The tool has zero parameters, and the empty schema is fully documented (100% coverage). The description reinforces this by saying 'List all environments', which implies no parameters are needed. The baseline score of 4 is appropriate for a parameterless tool.

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 environments via v1 endpoint', a specific verb+resource statement that clearly identifies the tool's function. It also distinguishes from the sibling v2 endpoint ('Simpler than msplatform/v2'), making the purpose unmistakable.

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 states 'Preferred for read-only discovery' and contrasts with the v2 'permission gate', giving clear guidance on when to choose this tool over the alternative. This is comparable to the high-scoring example that names an alternative.

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