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

Annotations already declare readOnlyHint/idempotentHint/non-destructive, so the remaining burden is low. The description still adds real value beyond them: the call is free, results are newest-first, the payload fields are id/what/network/date, and the list mirrors Analytics → Competition. It does not mention result limits or pagination, which keeps it off a 5.

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-loaded with what the tool returns and tightly written — every clause (cost, ordering, return fields, alternative) carries information. The parenthetical enumeration of analysis types makes the first sentence dense and slightly awkward, but nothing is padding.

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 correctly enumerates the returned fields and the ordering, and it covers the routing decision against three related tools. Missing only volume/pagination context (how many analyses come back), which matters little for a cheap read-only list.

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?

Only one parameter (workspaceId), and the schema documents it fully at 100% coverage, including the 'not needed when the connection is tied to one workspace' nuance. The description adds nothing about workspaceId, 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 concrete resource (previously run niche/account/reel analyses), its scope (per brand, across Instagram/YouTube/Reddit/X), and ordering (newest first). It also explicitly separates itself from get_research (single record) and research_niche/research_account (new work), so the agent can discriminate 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?

Gives an explicit precondition for use ('when the user mentions an earlier analysis'), names the two siblings to check against (research_niche, research_account), and points to get_research for the follow-up read. It even states the exclusion rationale: avoid paying twice.

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