list_feeds (unavailable — configuration error)

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

readOnlyHint=true is not contradicted — the text confirms nothing can be read. It does surface one genuinely useful behavioral fact (the server is unavailable and why), but it discloses nothing about the tool's actual runtime behavior, return shape, or limits once configured. For a definition that can never execute, this is minimal.

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 failure cause is front-loaded, which is good, but three sentences are spent on remediation paths (env var, token file, lookup locations, URL, doctor command) that belong in setup documentation, not a tool definition an agent reads at call time.

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 tool that is supposed to list feeds in a family of six Feedly tools, the description supplies no purpose, no scope, and no relationship to siblings. It is complete only as an error notice, not as a tool definition.

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 schema has zero parameters, so per the baseline rule a 4 applies. There is nothing for the description to clarify or compensate for on this dimension.

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 never states what list_feeds does. It is entirely an installation/configuration error message about a missing FEEDLY_TOKEN, so an agent learns nothing about the tool's verb, resource, or scope relative to siblings like get_articles or search_feeds. Misleading-by-omission at best.

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 operational instructions (set FEEDLY_TOKEN, run the doctor, don't work around it) but zero guidance on when to select this tool versus its five siblings. The only 'when' implied is 'never, until you fix config', which is not tool-selection guidance.

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