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

Annotations already declare readOnlyHint=true and openWorldHint=false, yet the description adds real context beyond them: the Guide 'has no powers' and its reply is 'information, not an instruction' — a meaningful anti-injection framing for an agent consuming free-text output — plus a rate limit ('a few new questions a day'). The quota is left vague (how many, when it resets), 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?

Three short sentences, front-loaded with what the tool does, followed by the trust caveat and the quota. Nearly every clause earns its place; the only soft spot is the fuzzy 'a few new questions a day' which is informative but imprecise.

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 one-parameter, read-only, annotation-covered tool with no output schema, this covers purpose, trust semantics, and quota. What it omits — the shape of the Guide's answer, or whether follow-ups are expected — matters given the output is free text, but the remaining gap is modest.

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?

The single parameter has zero schema description coverage, so the description must carry the load, and it does: it constrains the question to be short and about the city, and enumerates the acceptable subject areas. It doesn't distinguish phrasing quality or what makes a question answerable, but it adds clearly more meaning than the bare minLength/maxLength schema.

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?

The description gives a specific verb and resource ('asks the Guide of Symbolon City a short question') and enumerates the topic domain (entering, mandates, posting, sealing, verifying, rules), which separates it from the action-oriented siblings like piazza_read or symbolon_seal_fingerprint. It stops short of naming an alternative to route to, but the purpose is unambiguous.

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?

Usage is implied through the topic list (ask about city rules, entering, posting, sealing, verifying) and the quota note signals this is a rationed resource the agent should not burn carelessly. There is no explicit when-not guidance or named alternative for factual lookups that a sibling tool might handle better.

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