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

With no annotations provided, the description carries the full burden and does well: it discloses nightly recording, the start date (2026-08-27), coverage of every vendor Peptul tracks, and the metric definition (cheapest in-stock price per mg). It does not describe the exact response format or pagination, but the summary statistics are mentioned.

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 compact and front-loaded: the core definition comes first, followed by explicit usage guidance, and ends with an important data caveat. Every sentence earns its place and there is no redundant phrasing.

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 two-parameter tool with no output schema and no annotations, the description covers the purpose, the key metric, the data source and timeframe, and the distinction from the main sibling tool. The main gap is not spelling out the response shape, but the mention of period low/high/change gives a strong hint.

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 schema already documents both parameters. The description adds useful interpretive context about what the prices mean, but it does not add new per-parameter semantics beyond what the schema's descriptions already provide.

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 states a specific verb and resource: how a peptide's price has moved over time, with concrete details (cheapest in-stock price per mg each day, period low/high/change). It clearly distinguishes itself from get_compound_prices, which answers current cost, making the tool's purpose 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?

The description explicitly says 'USE THIS when asked whether a price is currently good, whether it has risen or fallen, or what a peptide usually costs'. It also names the sibling alternative, get_compound_prices, and explains the exact division of labor: that tool answers current price, this one answers whether that price is cheap.

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