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

Annotations only flag openWorldHint=true, destructiveHint=false, idempotentHint=false and readOnlyHint=false; the description adds the substantive context those flags lack — that this is live public data, that a fresh success costs the operation's credits (1, or 2+ for heavier ops), and that accepted cache hits and failures cost zero, which also explains the non-readonly annotation. It does not discuss rate limits, auth, or error payloads, so it is strong but not exhaustive.

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 cost model and the capabilities dependency are front-loaded and dense with useful information, with no filler sentences. The long platform enumeration ('TikTok, Instagram, Threads, Facebook, X, LinkedIn...') is partly redundant with the platform enum in the schema and is the one stretch that could be trimmed.

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?

For a generic dispatcher tool with a nested free-form params object and no output schema, the description covers what an agent needs to call it correctly: how to obtain valid platform/resource values, how params bind to the operation schema, and the credit consequences of a call. It leaves the response payload shape and failure semantics largely unexplained, which matters somewhat given there is no output schema.

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 the schema already documents platform, resource, params and freshness in detail. The description adds cross-field meaning — params are keyed to the selected operation's schema rather than to this tool's own schema — but otherwise repeats the schema's guidance, which is the baseline-3 case.

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 and resource ('Fetch any implemented public resource') and immediately ties it to the discovery sibling 'signalshelf_capabilities', showing the exact key format (platform "web", resource = "tiktok/video/comments"). The platform list makes the scope concrete enough that an agent can distinguish it from signalshelf_batch and signalshelf_capabilities without opening any 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?

The description establishes a clear prerequisite workflow: the resource must be one returned by signalshelf_capabilities, and params must match that operation's schema. It does not explicitly say when to prefer signalshelf_batch instead of calling this repeatedly, so the alternative-routing guidance is implied rather than stated.

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