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

The description adds real value beyond the readOnlyHint/idempotent/destructiveHint=false annotations by stating explicitly that it "opens nothing by itself" and returns instructions rather than performing an action — that removes the main ambiguity of a tool named "launch." The note about Privy's public API being on paid plans and the read-only MCP server adds operational context an agent would otherwise lack. It is consistent with the annotations.

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?

Action and its non-effect are stated up front, and the follow-up tool path comes immediately after; both are load-bearing. The final sentence about Privy's official API plan tiers and a dated "checked 23 Oct 2026" stamp is marginal filler that does not help the agent decide or invoke.

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 params, no output schema, and read-only annotations, the description carries the burden well: it says what comes back (screens, buttons, fields) and what does not happen (nothing is opened). The only gap is that the term "display" is never grounded, so an agent unfamiliar with Privy cannot be fully certain of the target object.

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?

Zero input parameters, so there is no parameter meaning to document — baseline 4 applies. The description correctly implies a parameterless call by describing the output as a fixed step-by-step walkthrough.

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?

"Launch display" is a vague, unexplained verb+object pairing — the description never defines what a "display" is in Privy. It does clarify the actual behavior (returns step-by-step instructions and "opens nothing by itself"), which rescues it from tautology, but an agent still has to infer the domain concept.

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?

It gives an explicit two-step workflow: call this to get the screens/buttons/fields, then execute with the cotlet_browser_* tools in the Privy Cloud Browser. That sequencing is genuinely useful. It does not say when NOT to use it or how it differs from a generic guide tool like cotlet_app_guide, so it stops short of full alternative routing.

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