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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower. The description still adds genuinely new context: the required scope read:inbox and that the call is free. 'Changes nothing' largely restates destructiveHint=false, which keeps it out of 5 territory.

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 short sentences, zero waste, with the core action and its required inputs front-loaded before the permission and cost notes. Every clause earns its place.

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 read-only tool with full annotation coverage and a fully described schema, the description supplies the missing pieces an agent needs: auth scope, cost, and the sibling that yields the ids. It omits any mention of pagination via cursor, but the schema covers that adequately.

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 coverage is 100%, so all three parameters (including cursor pagination) are documented in the schema itself. The description confirms the sourcing of conversationId and accountId but adds no syntax or format detail beyond what the schema already states, 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 and resource ('Read the full message history of one conversation') and names the sibling that supplies the required ids (soclo_inbox_list). An agent can distinguish it from soclo_inbox_list and the other inbox read tools 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 clear context for use: read one conversation, identified by a conversationId sourced from soclo_inbox_list, on an owned accountId. It doesn't state explicit exclusions (e.g., when to use soclo_inbox_list vs this), but the routing is unambiguous.

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