followings

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds a behavioral hint about an 'expiring local viewer receipt,' but it is vague and does not clarify expiration semantics, return format, or pagination behavior. No contradiction with annotations is present.

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?

The description is a single sentence and leads with the primary action and resource, which is appropriately front-loaded. The cryptic 'expiring local viewer receipt' phrase reduces clarity but not size or organization; there is no redundant filler.

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 and no parameter documentation, the description should explain what the tool returns and how to use limit/cursor. It does neither. The 'receipt' wording hints at a return artifact but not its structure, lifetime, or pagination behavior, leaving an agent under-informed for a straightforward list endpoint.

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 the description does not mention limit or cursor at all. Since the schema provides only types and constraints—not semantic meaning—the description was supposed to compensate but does not. An agent gets no help understanding pagination or how these parameters interact.

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 core action and resource are clear: 'Fetch followed users.' This distinguishes it from sibling tools like following_tracks and liked_tracks. However, the appended phrase 'into an expiring local viewer receipt' is opaque and adds ambiguity to what the tool actually produces.

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?

No guidance is given about when to use this tool versus alternatives such as following_tracks, get_profile, or connection_status. There are no exclusions, prerequisites, or explicit routing hints. The intended context must be inferred entirely from the tool name and the one-line description.

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