get_market_briefing

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

Annotations already declare readOnly, idempotent, not destructive. Description adds that it is cache-only (no API call) and describes return field behavior (null when caches absent). No contradiction. Adds valuable context beyond annotations.

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?

Description is well-structured with purpose, usage guidance, return details, and args in clear sections. Front-loaded with purpose. Some redundancy in listing return fields, but overall efficient for the tool's complexity.

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?

Given the tool's complexity (multiple return sections), presence of output schema, and annotations, the description is complete: it covers return fields, edge cases (null when cache absent), parameter details, and plan support. No major gaps.

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 0%, but description explains date format (YYYY-MM-DD or YYYYMMDD), sector_type default and options ('s33' or 's17'), and n default with range (1-100). Fully compensates for missing schema descriptions.

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?

Description starts with 'Daily market briefing' and lists specific content like ADR, sector ranking, top movers. It clearly distinguishes from siblings get_sector_briefing and get_stock_briefing, providing a specific verb-resource pairing.

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 states when to use (for market briefing, daily summary) and when not to use (use get_sector_briefing for sector valuation, get_stock_briefing for single stocks). Also mentions supported plans and that it is cache-only.

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