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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds that the call needs a key issued in the admin panel, which is useful auth context, but it doesn't disclose anything about rate limits, pagination, or the sensitivity of returning API keys.

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 tight sentences: return content first, diagnostic use second, auth note last. The 'api_key is required' clause is mildly redundant with the schema's required field, which keeps it from a 5.

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?

There is no output schema, but the description enumerates the returned fields, which compensates well. Combined with annotations covering the read-only profile, an agent has what it needs to invoke this correctly, though limit/key semantics could be richer.

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?

With one parameter at 100% schema description coverage, the schema already documents api_key (including the sk_live_ format). The description only adds where the key is obtained, which is marginal value over the structured field, so the baseline 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 clear verb+resource and enumerates the returned fields (tenant name, plan, limits, API key list), which is specific enough to distinguish it from the list_* and get_session/get_avatar siblings. It stops short of explicitly naming a sibling it overlaps with, so 4 rather than 5.

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 a concrete diagnostic trigger: 'when sessions or avatars cannot be created, check the limits here first.' That is actionable context without naming the alternative tools, so it is clear guidance but not a full when/when-not matrix.

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