Profile

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

Annotations declare readOnlyHint=false and idempotentHint=false, which could mislead an agent; the description preempts that by explaining these are read-like POST requests that do not publish to social platforms. It also discloses credit consumption, the confirm=true gate, and cache-vs-live behavior, all beyond what annotations provide.

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 dense sentences: the field list first, then the cost/safety caveats. Nothing is wasted, though the long field enumeration is slightly list-heavy for a description.

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, the description usefully enumerates what is returned (username, follower_count, is_verified, bio_links, etc.), and covers the credit/confirm constraints. It stops short of describing error or empty-profile behavior, but is otherwise sufficient for the call.

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 100%, so handle, account, confirm, and cache_max_age are already fully documented in the schema, including the enum and caching semantics. The description adds no parameter-level detail, 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 specific verb+resource ('Retrieves a Threads user's public profile') and enumerates the returned fields, which cleanly distinguishes it from siblings like threads_search_users or threads_posts. An agent knows exactly what this returns without opening a schema.

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 preconditions (requires confirm=true, consumes paid credits) but never states when to choose this over alternatives such as threads_search_users, which also take a handle-ish query. Usage is implied through the credit/confirm constraint rather than routed explicitly.

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