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

Annotations already declare read-only, idempotent, non-destructive and closed-world, so the description is not carrying the safety burden. It nonetheless adds genuinely new context: the result is an 'opaque session context' (important since there is no output schema) and the tool has 'app-only visibility,' a meaningful authorization constraint. It does not say what happens on failed revalidation.

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 short sentences that front-load the role, then the timing condition, then the return shape and visibility. Every sentence carries information, though 'Component helper' and 'opaque' are mildly jargon-heavy phrasing.

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 zero-parameter, read-only helper with complete annotations, the description covers purpose, timing, return nature, and visibility scope. The only notable gap is failure behavior when revalidation does not succeed, which an agent would want to know.

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, so there is nothing for the description to disambiguate; the baseline for a parameterless tool applies. No parameter text is needed and none is present.

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?

The description states a concrete verb and resource — revalidating the current Joe Speaking connection — and reconciles the 'get_coach_authorization' name by noting it returns an opaque session context. It distinguishes the tool's role from siblings like open_joe_speaking or get_joe_speaking_practice_link, though the framing as a 'Component helper' is slightly internal-sounding.

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 trigger: call this before the coach reuses private evidence. That is clear conditional context rather than mere implication. It does lack exclusions or a named alternative (e.g., what to call if revalidation fails), which keeps it below a 5.

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