Resolve a username or id

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so safety is covered. The description adds that the result is a 'chat you can act on', which hints at the return type. However, it doesn't disclose edge cases (e.g., unresolved identifiers) or any limitations beyond annotations. Since the description carries minimal extra behavioral info, a 3 is appropriate.

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?

Two sentences, no filler, and the core purpose is front-loaded. Every word earns its place, and it's easily scannable for an agent.

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 single-parameter, read-only, idempotent resolver with no output schema, the description covers the use case and hints at the return value ('chat you can act on'). It doesn't mention error handling or fallback behavior, but given the simplicity and annotation coverage, it's sufficiently complete.

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 schema provides 100% coverage for the single parameter 'peer' with its own description listing accepted formats including 'me'. The tool description merely repeats the same formats without adding new meaning. With full schema coverage, the baseline is 3, and the description adds no extra value here.

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 clearly states the verb 'resolve' and the resource (username/phone/id into a chat), and explicitly positions it as a step before sending. It distinguishes itself from siblings like get_chat or search by focusing on converting a handle into an actionable chat.

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?

The description gives a clear when-to-use: 'Use it before sending to someone you only know by handle.' It doesn't name alternatives explicitly, but the context implies that if you already have a chat reference, you wouldn't need this. This is adequate guidance for an agent.

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