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

Annotations declare readOnlyHint=false, openWorldHint=true, destructiveHint=false, so the write/external nature is partly covered. The description adds material context beyond them: an email is sent to the user as a side effect, the operation is step one of a two-step auth handshake completed by connect, and it handles both new and existing accounts. It stops short of describing failure modes or what the call returns, so it is not exhaustive.

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?

Front-loaded with purpose followed by actionable instructions in a logical order; every sentence drives agent behavior. Slightly longer than strictly necessary, with the rationale clause and the repeated email warning adding mild redundancy, but there is no filler.

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?

For a multi-step signup tool with annotations and an output schema already present, the description supplies everything an agent needs: the prerequisite user input, the side effect, the follow-up call to connect, and the key prohibition. Return-value details are correctly left to the output schema.

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%, so all three parameters are already documented, including the 'never guess' constraint on email that the description restates. The description adds no syntax, format, or value guidance for email/name/client beyond what the schema provides, so the baseline of 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 ('Create a CortexPlus account, or begin signing in to an existing one') and immediately names the sibling it hands off to ('call connect with it'). An agent can distinguish this from connect, recall, or remember without opening any 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?

Gives explicit context for use ('so this conversation can use CortexPlus as the user's long-term memory'), a step-by-step protocol (ask for email/name, then call, then collect the emailed key and call connect), and an explicit prohibition ('Never guess or invent the email address'). The alternative tool and the condition that triggers it are both named.

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