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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered; the description adds real value beyond that by disclosing that connection settings and credentials are redacted in the response. It does not discuss pagination or rate limits, which keeps it short of a 5.

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?

A single front-loaded sentence carries the purpose, the parenthetical definition, the returned fields, the redaction caveat, and the underlying endpoint. Dense but not padded; the field enumeration is the only element that could be argued as over-specified for a no-arg list call.

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 usefully compensates by enumerating the returned shape (id, name, source type, status, feeds) and flagging redacted credential fields, giving the agent enough to act on the result. Minor gaps: no ordering, pagination, or volume expectations.

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?

The tool takes zero parameters, so the baseline of 4 applies; there is nothing for the description to clarify beyond confirming it is a bare list operation with no filtering inputs.

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 ('List the data sources') and immediately defines what a data source is ('connections to third-party monitoring or custom push sources used for traffic steering'). This distinguishes it from ns1_get_data_source (singular fetch) and ns1_list_data_feeds.

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?

Usage is implied by the plural 'List' naming versus sibling ns1_get_data_source, and the endpoint is given, but there is no explicit statement of when to prefer this over ns1_get_data_source or ns1_list_data_feeds, nor any prerequisites noted.

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