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

Annotations already establish read-only, idempotent, non-destructive behavior, so the safety profile is covered. The description adds genuinely useful non-inferable context: all six platform arrays are always present even when empty, Facebook entries are Pages and Pinterest entries are boards (each board its own account). It stops short of describing auth/scope requirements or whether pagination applies.

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?

Front-loads purpose in the first clause, then the ID-contract in the second sentence, then edge-case notes. Three sentences, no filler. The parenthetical platform enumeration and the Facebook/Pinterest clarifications are dense but each carries information an agent needs.

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?

An output schema exists, so return-value structure need not be restated; the description correctly focuses on the non-obvious contract (IDs fed into selectedAccounts) and the empty-array invariant. Combined with annotations covering safety, an agent has everything needed to call and consume the result.

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?

Zero parameters, so the baseline is 4. The description instead invests in return-shape semantics (selectedAccounts ID contract, accountType values 'page' and 'board'), which is relevant for a no-param list tool even though a detailed output schema exists.

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 ('List the connected social accounts in your workspace') and adds a meaningful grouping dimension ('grouped by platform') with the exact platform keys enumerated. Clearly distinguishable from siblings like postnitro_get_social_account (singular, by ID) and postnitro_list_brands (different resource).

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?

Explicitly states the downstream use: 'These account IDs are what you pass as selectedAccounts when creating a scheduled post,' which routes the agent to postnitro_create_scheduled_post. It does not, however, contrast with postnitro_get_social_account or postnitro_disconnect_social_account, so an agent must still infer which list-vs-single tool to pick.

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