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

Goes well beyond the annotations: it discloses that an Ed25519 key is generated per connection with the private half retained server-side, that keys are cached ('same key comes back until a connection uses it or a week has passed'), that authorizedKeysLine is only produced when host and port are supplied, and the permission model ('Owners, admins and editors'). readOnlyHint=false is consistent with key generation, so no contradiction.

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 purpose and the sibling relationship are front-loaded in the first clause, followed by return values, caching behavior, and permissions in a logical order. Every sentence carries a distinct fact — no filler or restated title text.

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?

There is no output schema, and the description fully compensates by naming all three returned fields and explaining when authorizedKeysLine appears. Combined with the caching window and role requirements, an agent has everything needed to call this correctly and to sequence it with fastero_create_connection.

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 coverage is 100%, so baseline would be 3, but the description adds semantics the schema does not: host and port are optional and exist solely to fill in authorizedKeysLine, and are therefore unnecessary if the caller only needs the key. That is a real behavioral consequence of the parameter values, not a restatement.

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 and resource ('Get the SSH key') scoped to 'a new connection to a database behind an SSH bastion (jump host)'. It also names the adjacent sibling (fastero_create_connection) and the condition that removes the need for this tool ('a database Fastero reaches directly needs none'), so an agent can distinguish it without opening a 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?

Gives explicit ordering ('before fastero_create_connection'), an explicit exclusion ('a database Fastero reaches directly needs none'), and the downstream handoff ('fastero_create_connection then takes the sshKeyId in creds'). When, when-not, and how it chains are all stated.

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