list_serial_ports

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

With no annotations provided, the description carries the full burden and does reasonably well: it discloses a hard 100-port output cap, that all supplied filters are AND-combined, and the important side-effect guarantee that discovery never opens a serial port. It omits permission/auth requirements and what happens when the 100-port cap truncates results.

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 compact sentences, front-loaded with purpose and then the filter grammar. No filler, every clause carries operational meaning.

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?

An output schema exists, so return-value explanation is not required, and the description covers filters, combination logic, the result cap, and the non-opening guarantee. The only gap is that the 100-port limit is not framed as truncation or pagination, leaving unclear how an agent retrieves ports beyond the cap.

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%, so the description must compensate, and it does: it defines match as a case-insensitive substring over port/description/board hint/location, vid/pid as exact integer USB IDs, serial_number as an exact USB serial, and states that filters combine. Every one of the four otherwise-undocumented parameters is fully specified.

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 opens with a specific verb+resource ("Discover boards") that maps directly to enumerating serial ports, and the filter semantics make the scope unmistakable. It does not name or contrast any sibling tool, but the resource is distinct enough from list_boots/list_capture_sessions/describe_capabilities that confusion is unlikely.

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?

"Discover boards; filter before limiting output to 100 ports" gives implied guidance on when to reach for this tool and on filtering first, but it never names an alternative or an explicit when-not-to-use condition. There is no routing advice toward siblings like describe_capabilities or query_logs.

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