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

Annotations declare readOnlyHint=false, idempotentHint=false, openWorldHint=true, and destructiveHint=false, so the safety/mutation profile is already covered. The description adds only 'Storage charges may apply,' a useful cost warning, but omits permissions, side effects on the volume, and backup lifecycle behavior.

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 short sentences, front-loaded with the core action and followed by a material caveat. No filler, and the cost note earns its place.

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?

With 9 parameters, 0% schema description coverage, and no output schema, the description is too sparse to help an agent call the tool correctly. It gives purpose and cost but no parameter meaning or success/return context.

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% across 9 parameters, and the description names none of them. It does not explain volumeInstanceId (the sole required parameter), the optional name, or the beon_* / approval_id fields, so it adds no semantic meaning beyond the schema.

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?

States a specific verb ('Create') and resource ('persistent volume backup'), distinguishing it from sibling railway_create_volume and railway_restore_volume_backup. An agent can identify the operation without opening the schema.

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 on when to use this tool versus alternatives such as railway_list_volume_backups, railway_restore_volume_backup, or railway_lock_volume_backup. The only context is the cost caveat, which does not help selection.

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