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

Annotations already establish readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description still adds real behavior beyond that: cursor-based pagination ('Pass next_cursor back as cursor for the next page') and an auth precondition ('Cotlet API key with access to this app').

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?

Front-loaded with the resource and returned fields, and each sentence carries functional information (search behavior, downstream ID usage, pagination). Slightly redundant where 'A contact is a client, a supplier or both' repeats the kind enum meaning, but overall tight.

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?

With no output schema, the description compensates by naming the returned fields (name, tax ID, email, phone) and the contact_id/next_cursor fields an agent needs. It omits page-size defaults and total-count behavior, but nothing essential for a correct call 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 description coverage is 100%, so the baseline is 3. The description largely restates schema semantics ('Search matches the name or the identification number', 'A contact is a client, a supplier or both' mirrors the kind enum) rather than adding format or default detail beyond the schema.

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 ('Lists contacts'), clarifies the domain (clients and suppliers) and enumerates the returned fields. It names related siblings (create_invoice, list_invoices) but does not clearly contrast itself against the other contact-listing tools across sibling apps, so it stops short of full differentiation.

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 useful operational context — search matches name or tax ID, and contact_id feeds create_invoice/list_invoices — which implies the reason to call it. However, it never states when to prefer this over alegra_create_contact or how to retrieve a single known contact, so it is implied rather than explicit routing guidance.

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