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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered by structured data. The description adds real context beyond that — that these helpers are re-asserted into every generated app and that lookups return props/signature — but says nothing about result size, latency, or what a miss returns.

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 dense paragraph, front-loaded with the verb and resource before the enumeration. The long component list is justified because exact membership is what the agent needs, but the sentence is packed and could have been split for scannability.

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?

No output schema exists, so the description must carry return-value semantics; it does so at a high level ('exact props/signature'). Combined with the usage rules and mode selection, an agent has enough to call this correctly, though the shape of the returned signature data is unspecified.

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% and neither parameter is documented in the schema, so the description carries the full burden. It does this credibly: name = precise lookup, query = fuzzy search, neither = list all. It stops short of giving format details (e.g. path-style vs bare component name).

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 precise verb ('Look up') and a well-defined resource ('x engine-owned ./final/* helper') and then enumerates the exact component surface (Button, Card, Dialog, usePrint, Barcode, etc.), so an agent knows exactly what it will retrieve. It is clearly distinguishable from sibling lookups like flow_lookup_command_frame and flow_lookup_pos_api, which target different surfaces.

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?

Gives strong prescriptive guidance: compose screens from the primitives, import the rest, and stop hand-rolling buttons/cards/dialogs, printing, station-home, barcodes or splash. It also routes the agent between modes (name for precise lookup, query for fuzzy, neither to list all). It does not explicitly contrast itself against sibling lookup tools, so it falls short of a full 5.

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