mayotte_fetch_source_excerpt

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

With no annotations provided, the description must carry the transparency burden. It adds 'short excerpt' and 'curated source' context beyond the schema, and hints at a simple read operation. However, it does not disclose potential side effects (unlikely), error behaviors (e.g., if URL is not found), or any rate limits. Since this is a simple read, the level of disclosure is adequate but not exceptional.

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 two concise sentences that front-load the primary action and then provide a key detail about parameter usage. Every word earns its place; there is no redundancy or filler. It perfectly balances brevity with necessary information.

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 simplicity of the tool (2 parameters, no output schema), the description is relatively complete. It covers the core purpose, hints at the source of source_key, and implies a read-only operation. The only minor gap is that it does not describe the return format edge cases, but for such a simple fetch tool, this is acceptable.

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 description coverage is 100%, so baseline is 3. The description adds value by clarifying that source_key can be 'a number' (interpreting 'index') and connects it to `get_sources`, which is not explicit in the schema. This extra guidance helps agents understand the accepted formats without additional lookups.

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 the tool fetches a short text excerpt from one curated source URL. It uses a specific verb ('Fetch') and resource ('short text excerpt' from a curated source), and distinguishes itself from siblings like `get_sources` by focusing on the excerpt itself. The reference to `get_sources` further differentiates it as the next step in a workflow.

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 implies usage context by stating the source_key comes from `get_sources`, but it does not explicitly say when to use this tool over siblings (e.g., when you need a quick excerpt vs. full metadata). It gives some guidance on the source_key format but lacks clear 'use this when' or 'alternatives' language, so it falls to implied usage.

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