spec_nav_services

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

With no annotations, the description carries the full transparency burden. It does disclose the shape of the response (services values, file/function counts, coverage summary), which is valuable given there is no output schema, but it never states that the call is read-only, whether it hits the filesystem/network, or any cost/latency characteristic.

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?

Two sentences, zero filler, and the return content is front-loaded before the usage note. Every clause earns its place.

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 zero-parameter read tool with no output schema, the description supplies both the return contents and a routing rule, which is enough for an agent to call it correctly. The only gap is the absence of any safety/read-only statement, which matters because annotations are absent.

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 schema baseline of 4 applies. No parameter information is needed or expected in the description, and the description correctly says nothing about arguments.

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 states a concrete resource and payload: the projects under the root exposed as `services` values, plus file/function counts and a coverage summary. It is clearly a discovery/listing tool, though it never names the sibling tool it complements (e.g. spec_nav_map), so differentiation is inferred rather than stated.

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?

It gives an explicit when-to-use ('unsure of service names or whether SPEC_NAV_ROOT is right') and an explicit when-not ('not needed otherwise'), which is stronger than most siblings. It stops short of naming the alternative tool to use once the names are known, so it is not a full 5.

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