mac_apps

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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety bar is covered. The description adds genuinely useful behavioral context beyond that: what 'presentation' means (Dock vs menu-bar/agent app) and, importantly, that helper processes are excluded unless all:true — a non-obvious scoping rule that changes 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?

Two dense sentences with zero filler, front-loaded with the action and output shape, then the parameters. Every clause conveys operative information the agent needs.

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 listing the returned fields; with only two optional params and full annotation coverage, little else is required. The missing higher-level 'when to prefer this over mac_app/mac_windows' is a minor omission, not a blocker.

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 carry the parameters, and it does explain both: filter matches the name OR bundle id, and all:true widens the result set to helper processes. Remaining gap is match semantics (substring vs exact, case sensitivity), which is why this isn't a 5.

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 ('List running apps') and even enumerates the returned fields (name, pid, bundle_id, presentation, frontmost, hidden), so the agent knows exactly what it gets. It does not explicitly contrast itself with nearby siblings such as mac_app or mac_windows, which keeps it short of a 5.

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?

Usage is implied rather than stated: an agent infers this is the enumeration step before targeting an app via mac_app/mac_window. There is no explicit 'use this when…' or exclusion guidance, but the two parameters (filter, all:true) implicitly signal the two supported retrieval modes.

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