get_default_key_replication_regions

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

With no annotations, the description carries the full behavioral burden. It clearly frames the operation as a read-only inspection ('Call this to see') and adds meaningful semantic context about account-level defaults and inheritance for keys created or imported without explicit replication_regions. It does not mention output shape or permissions, but for a zero-parameter read operation this 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?

Two concise sentences deliver the core action first, followed by the key semantic detail about inheritance. No filler or redundant wording.

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 zero-parameter getter with no output schema, the description is complete. It tells the agent why to call it, what it observes, and how the observed default behaves. Nothing essential is missing.

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, so the baseline is 4. The schema is already complete with an empty properties object, and the description adds relevant context about what the default applies to without needing to explain any parameter syntax.

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 states a specific verb and resource: 'see which regions new keys replicate into by default.' It also distinguishes this read-only getter from sibling enable/disable tools by framing it as an inspection action rather than a configuration change.

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?

The description gives explicit usage context: 'before creating keys or when auditing why a key landed in a region you did not expect.' It does not explicitly name alternatives or exclusions, but the context is clear enough for an agent to decide when this tool is appropriate.

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