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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered; the description adds real value beyond that by stating what is displayed and the privacy trait 'verified wallets (summarized, never full addresses)' plus an explicit no-custody statement. It does not address auth/connection prerequisites or any latency/refresh behavior, so it falls short of a 5.

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 sentences, front-loaded with the action and trigger before the detail dump. Every sentence carries information, though the final no-crypto disclaimer is slightly verbose for a read-only viewer.

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 an output schema present, return values need not be spelled out, and annotations carry the safety profile; the description still covers purpose, contents, triggers, and the no-custody boundary. The only gap is the undocumented workflow parameter, which would let an agent route directly into a sub-workflow instead of the home view.

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 100% and the single optional enum parameter is documented in the schema, so the baseline of 3 applies. The description never mentions the 'workflow' parameter or that it can jump straight into buying_power, verify_wallet, or proof_of_funds, missing an opportunity to explain the enum's effect.

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?

Names a specific verb and resource ('Opens the RealOpen home, the full-screen app in the ChatGPT sidebar') and immediately enumerates what the surface shows, so an agent can distinguish the overview from action tools like check_buying_power or generate_proof_of_funds. It stops short of naming the nearest sibling (open_buying_power_panel) or clarifying the overlap with the workflow parameter.

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 explicit invocation triggers: 'when the user asks to open RealOpen, open the RealOpen app or sidebar, or see an overview of where they stand.' It also draws a boundary with 'purchase funding is coordinated on RealOpen outside ChatGPT,' which tells the agent this is not a transaction entry point. No explicit when-not-to-use vs. the workflow siblings, though.

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