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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world; the description reinforces the last point with 'Reads Royally's records only.' It adds valuable behavioral detail beyond annotations — the with/without site_id result shape and that client is null when a site has none — but does not discuss pagination or payload size.

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 what the context is, then the usage directive, then the two result shapes. Every sentence carries information; the only mild cost is that the long opening sentence packs many clauses together.

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?

No output schema exists, so the description carries the return-value burden, and it does describe both branches of the result including the null-client edge case. It stops short of naming the exact fields an agent should expect, leaving some ambiguity about the response envelope.

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 the schema documents site_id and points to fleet/list_sites. The description still adds semantic value by explaining the consequence of omitting the parameter (agency context plus every client that has context), which the schema does not convey.

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 (read) and resource (AI agent context) and enumerates the two content types it returns: agency house rules (agency_notes) and per-client context such as brand colors, tone, and contacts. An agent can distinguish this from siblings like fleet__list_sites or royal-mcp__wp_get_site_info without opening the 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?

Explicitly prescribes when to call it ('Read it before changing a site's content or design') and gives a precedence rule ('follow it unless the person you are working with says otherwise'). It also spells out the two calling modes: with site_id vs. without site_id and exactly what each returns.

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