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

Annotations already cover the safety profile (readOnlyHint, destructiveHint=false, openWorldHint=false), so the description focuses elsewhere and usefully discloses output contents (id, network, type, name), the current single-network limitation, and a security-relevant fact: 'Never returns LinkedIn tokens.' That is real extra context beyond the annotations.

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 sentences, front-loaded with what the tool does, then output shape, then the key integration fact. The parenthetical 'more networks later' is mild filler but contextually useful for future-proofing; otherwise there is little waste.

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 must carry return-value semantics, and it does: it enumerates the returned fields, gives the concrete 'personal' id example, and explains how those ids are consumed. Nothing an agent needs to call or interpret this tool is missing.

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?

There are zero input parameters, so the baseline is 4. The description instead clarifies output-parameter semantics, explaining the meaning and downstream use of the returned destination ids — more than the empty schema provides.

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 (lists) and resource (destinations this account may post to), and clarifies scope relative to siblings by noting the ids are the values the destination parameter of the other tools accepts. An agent can immediately tell this is the read-only lookup that feeds the publish/upload tools, not one of them.

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?

Implies the use case clearly: call this to discover destination ids before invoking the posting tools that take a destination parameter. It gives solid context but never explicitly says 'call this before publish_now/schedule_post' or states any exclusion, so it stops short of full when/when-not guidance.

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