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

Annotations declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is mostly covered. The description adds the useful scoping note that it does not touch schedule data, which reconciles the read-only hint with the verb "bind", but it says nothing about permissions, the open-world behavior it triggers, or persistence.

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, front-loaded sentences with the key qualifier ("App-only") first and the negative constraint last. No filler, though it is arguably under-specified rather than maximally concise.

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 two-parameter tool with no output schema and no parameter docs, the description leaves major gaps: what plan is, what participant_id is, and what binding produces. The annotations carry safety but there is no return or behavior detail.

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 0% and both required parameters (plan, participant_id) are undocumented in the schema. The description vaguely refers to "the name" but never explains what plan or participant_id are or how they relate to the selected name, so it fails to compensate for the coverage gap.

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?

It labels itself an "App-only identity picker" and says it binds the name selected in the shared web UI, which conveys the general intent. However, the operative verb is ambiguous ("bind") and it never states what resource is being set (a session identity? a plan participant?) in a way that clearly separates it from siblings like widget_lookup or join_plan.

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?

"App-only" and "explicitly selected in the shared web UI" imply the context in which this applies, and "Does not change schedule data" rules out one class of expectations. But no alternative tool is named and there is no explicit when-to-use/when-not statement.

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