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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered; the description adds genuinely new behavior: vault secrets and keys are never included, the returned fields are enumerated, and the not_installed failure mode is documented. The only gap is that it doesn't say whether collection data can be large or truncated.

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?

The purpose is front-loaded in the first clause, followed by return contents, filtering, exclusions, downstream use, and error mode in a compact run. No sentence is redundant with the schema or title.

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 carries return-value explanation and does so thoroughly, plus an error contract. Minor omissions (whether data volume is bounded, whether the session must be active) keep it from a 5 for a read tool with a rich payload.

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 coverage is 100%, so both parameters are already documented, including the 'Default: every spec app' behavior for ids. The description restates the ids filtering semantics ('Pass ids to export only some') but adds no format, size, or id-discovery guidance beyond the schema, so 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?

States a specific verb and resource ('Copy the spec apps ... out of the phone') and anchors the resource by origin ('made with create_app'), which separates it cleanly from import_phone_apps, list_apps, and export_test. An agent can identify the operation without opening the schema.

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?

Explains the partial-export case ('Pass ids to export only some') and the downstream pairing ('Give the result to import_phone_apps on another phone to recreate the apps'), which gives clear context for when this tool is the right call. It stops short of explicit exclusions, e.g. when to reach for list_apps or find_apps first to obtain ids.

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