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

Annotations already mark it read-only; the description adds valuable context: 15-minute server-side caching, Pro access requirement, and that the output includes both prose and a structured `data` payload. This goes beyond what annotations provide.

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 description is concise yet information-dense. Every sentence earns its place: purpose, output format, caching, REST mirror, access level, and disclaimer. No redundancy or filler.

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 tool with one optional parameter, read-only annotation, and no output schema, the description covers all essentials: return format (markdown plus data), freshness (caching), access restriction (Pro), and limitation (AI-generated, not advice). It is fully adequate for correct invocation.

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?

With zero schema description coverage, the description compensates by implicitly defining 'coin' via 'state of <coin>' and the REST path. It doesn't enumerate possible values or mention the default BTC, but the schema already provides the default, and the parameter's intent is clear.

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 clearly identifies a tool that generates a markdown prose brief for a specific coin, synthesizing multiple data sources into a quotable analysis. It explicitly distinguishes itself as the narrative layer over get_state, making it distinct from sibling tools.

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?

It states the tool produces a quote-ready narrative and mirrors REST /state/{coin}/brief, implying use for human-facing summaries. It mentions the Pro requirement and 'not advice' caveat, but stops short of explicitly saying when not to use it or naming alternatives beyond get_state.

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