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

Annotations already declare readOnly/no-destructive/no-openWorld, but the description adds real behavioral context beyond them: 'unmetered, no side effects,' and the failure contract that any unreadable section returns its own {error, detail} instead of silently vanishing. That error-shape disclosure is exactly the kind of detail annotations cannot carry.

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 the tool's role, then a single dense sentence enumerating the return contents. The long parenthetical list is information-dense and each item is useful, though the enumeration is heavy enough to slightly dilute 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?

With no output schema, the description carries the full burden of describing return values, and it does so thoroughly: identity, deal counts and newest-with-links, personal counts, ranked next_actions with their connections_execute calls, and the voice summary. An agent knows precisely what it will receive.

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?

The tool takes zero parameters and the schema is empty, so there is nothing to disambiguate; baseline 4 applies. No param meaning is required or missing.

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 role ('the session opener') and enumerates exactly what one read returns: identity/company binding, live deals with counts, contact and event counts, ranked next_actions, and a voice summary. It also differentiates itself from connections_whoami by noting it carries that answer inside it.

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?

Calling it 'the session opener' plus the note that it subsumes connections_whoami gives clear implied usage at session start. It stops short of an explicit when-not-to-use rule or naming alternatives for specific sub-reads, so it isn't a full 5.

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