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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds real behavioral context the annotations cannot: a 90-day window and downsampling to at most 60 points. It does not mention error behavior for invalid ids or rate limits, which keeps it from 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?

Two sentences, both dense and front-loaded: the return shape first, the prerequisite routing second. No filler and no repetition of the tool name.

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?

An output schema exists, yet the description still summarizes the computed fields so the agent knows what the call yields; combined with full schema coverage and annotations, nothing needed to invoke it correctly is missing.

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 baseline is 3; the schema already documents id, days, variant, and response_format. The description restates the 90-day cap and adds the downsampling behavior, but says nothing extra about variant semantics or what changes between concise and detailed beyond what the enum already conveys.

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 names a specific verb and resource (daily USD price series for one card) and enumerates the deliverables (start, end, change, high, low, trend). It is clearly distinguishable from browse/search siblings, though it never contrasts itself with the close cousin binderdex_get_price_stats.

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?

Gives an explicit prerequisite: 'Call binderdex_search_cards first if you only have a card name,' which tells the agent how to obtain the required id. It stops short of stating when to prefer this over binderdex_get_price_stats or binderdex_get_market_movers.

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