list_instances

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

With no annotations and no output schema, the description carries the full burden and does disclose the shape of the result plus the meaning of the 'active' field, which is genuinely useful semantics beyond structured data. It omits permission requirements, whether there is any side effect, and any relation to the instance_id routing requirement, so it is not complete.

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?

Three short sentences, front-loaded with the operation and then the usage context, with no filler. The second sentence slightly restates the 'reachability status' idea already implied in the first, a minor redundancy.

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?

Covers return fields adequately given there is no output schema, but for a required-instance_id tool it omits how an agent obtains that ID and how this differs from instance_list/instance_info, both of which are live siblings performing overlapping work.

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 there is a single required parameter, so the baseline is 3; the description adds nothing about instance_id beyond what the schema says. Notably, the description never mentions that an instance_id must already be known, which is the tool's sole input.

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 ('List all discovered IDA Pro instances') and enumerates the returned fields (binary name, port, reachability status). An agent understands the operation immediately, but the description never differentiates this tool from the near-duplicate sibling 'instance_list', leaving ambiguity about which to call.

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?

One sentence gives context ('Use this to see which IDA databases are currently open and available for analysis'), which implies when to use it. However, it gives no when-not guidance and never addresses the obvious alternative 'instance_list' (or 'instance_info'/'select_instance'), even though the sibling set contains a highly similar name.

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