get_market_brief

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

No annotations exist, but the description thoroughly covers behavioral traits: it is deterministic (no forward-looking probabilities), cached per day, and returns a composite snapshot. It does not mention side effects, but none are expected for a read operation. The description compensates well for the lack of 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?

The description is dense (about 150 words) but well-structured: purpose first, then usage, then deterministic nature, currency details, comprehensive list of return bundles, sibling differentiation, and caching. Every sentence adds value, though slightly more conciseness could be achieved.

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 no output schema and two optional parameters, the description provides a full picture: what the tool does, when to use it, what it returns (detailed bundle list), its deterministic and cached behavior, and how it relates to sibling tools. It is comprehensive for a complex diagnostic tool.

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?

Both parameters are documented in the schema (100% coverage), and the description adds value by explaining display_currency's role ('USD = no FX line') and listing allowed currencies. It also clarifies refresh as 'force regenerate, bypass today's cache'. This enriches the schema definitions.

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 states it is a 'composite read of *current* portfolio state' and differentiates from siblings like project_net_worth (probabilistic projections) and show_* tools (drill-downs). It uses a specific verb (read) and resource (current portfolio state), making the purpose unmistakable.

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?

The description explicitly advises 'Call this FIRST' and explains that it obviates multiple tool calls for common questions. It provides direct alternatives: use project_net_worth for probabilistic projections and show_* tools only for detail when needed. This is exemplary usage guidance.

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