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

Annotations already cover destructiveness (false) and world scope (false), so the description's main added value is the fixed $0.50 per-call price and the 'material differences' output focus. It does not contradict the non-read-only annotation; the paid-per-call model is consistent with readOnlyHint=false. It stops short of describing output format or latency.

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?

Three short sentences, front-loaded with the core action. The pricing sentence interrupts the flow slightly but is short and relevant.

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 single-parameter comparison tool with no output schema, the definition covers purpose, price, and a use case. It is still missing the key operational detail — the required format of each document string — and any hint about the shape of the returned differences.

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% and the single `documents` parameter is an untyped array of strings. The description implies the array should contain exactly two contracts, which is useful, but it does not say whether these are IDs, file paths, URLs, or raw text — the caller still has to guess.

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?

States a specific verb and resource ('Compare two contracts') plus the output intent ('show material differences'). It is distinguishable from fikra_summarise_contract and fikra_analyse_contract_risks, though it never explicitly names those siblings.

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?

'Checking a redline actually changed what was agreed' supplies a concrete use case, which is better than nothing. However, there is no explicit when-not guidance and no named alternative (e.g., summarise_contract for a single document).

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