get_instance

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint, so the safety profile is covered. The description adds only a brief return note ('Returns JSON with full instance details including health indicators') with no detail on error behavior, permissions, or response shape beyond that; with no output schema this is useful but thin.

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 sentences, both front-loaded with the core action and then the use case/return, with no filler or repetition beyond a minor overlap between 'metadata' and 'full instance details.'

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 no output schema, the description does supply a brief statement of what is returned, and annotations cover the safety profile, so an agent has enough to call it. It remains slightly incomplete on return structure and failure modes, but 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?

Schema description coverage is 100% and all three parameters are documented in the schema (region, account, instance_id with examples). The description only restates the identifying keys without adding format or constraint meaning, so the baseline 3 applies.

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 ('Get details for a specific compute instance') and names the three identifying keys, making it clearly distinct from resource-oriented siblings like get_cluster or get_account. It stops short of explicitly naming an alternative sibling tool, so it does not reach the top of the scale.

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?

'Use this to inspect instance health, metadata, launch time, and cloud-specific attributes' gives a clear, concrete use context. However, it offers no when-not-to-use guidance and does not point to any alternative tool for related lookups.

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