list_csm_contacts

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the description only needs to add context. It adds the filtering capabilities, but does not disclose any behavioral nuances like return format, pagination, or default ordering. This 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 a single, front-loaded sentence that efficiently conveys the tool's purpose and two main modes. Every word is necessary, with no redundancy or fluff.

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 simple list operation with well-documented parameters and full annotation coverage, the description is complete. It explains the dual functionality. However, it could mention the default limit of 25 or the fact that the output is a list of contact records, but given no output schema, this is minor.

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%, with all three parameters already described in the schema. The description reiterates the account and search functionality without adding additional meaning or usage details beyond what the schema provides.

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 'List contacts for an account or search across all contacts' clearly states the verb (list) and resource (contacts), and distinguishes two main use cases (account-specific vs. global search). This differentiates it from sibling tools like get_csm_contact (single contact) and other list tools.

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 two usage modes (filter by account or search), but does not explicitly state when to use each, nor provides guidance on when not to use or alternatives. It lacks criteria for choosing between this and similar tools like list_csm_accounts or search functions.

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