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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds valuable behavioral context by enumerating the returned detail fields (status, ip, region, instance_type, ssh/filesystem attachments, jupyter url, available actions) and naming the underlying REST operation, though it does not cover auth requirements or error 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?

A single front-loaded sentence communicates purpose, key, and return contents, followed by a compact REST endpoint reference. No filler, no repetition, and every clause 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 no output schema, the description compensates by enumerating the fields returned, and the readOnly annotation covers the safety dimension. An agent has everything needed to select and invoke this tool correctly for a single-instance lookup.

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% with one well-described id parameter, so the schema does the heavy lifting. The description restates 'by id' but adds no syntax, format, or source guidance beyond what the schema already provides, matching the baseline of 3.

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 (Get) and resource (a single instance) with a clear lookup key (by id), and the parenthetical enumerates exactly what 'full details' includes. This distinguishes it from sibling list_instances and other get_* tools without requiring schema inspection.

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 implies usage for retrieving one instance by id, but never explicitly states when to choose this over lambda_list_instances or lambda_list_instance_types, nor any exclusions or prerequisites. Usage is inferable but not guided.

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