Install (download) a HACS repository

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

Annotations already declare destructiveHint=true and readOnlyHint=false, and the description adds real value on top: it discloses that files are written to the config directory, that HACS entities get reloaded for brand-new integrations, and that a restart is conditionally needed. It does not say what an update overwrites or whether a failure leaves partial files, which is the main remaining gap for a destructive write.

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?

Three dense sentences with the core action front-loaded, followed by accepted inputs, then prerequisites. Every sentence carries information, though the restart caveat and auth requirement could be trimmed slightly for a tighter read.

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?

No output schema exists, and the description covers the essentials an agent needs: write semantics, auth scope, accepted identifier forms, and post-install behavior. It stops short of describing the return payload or what happens on a failed download, which keeps it from a 5.

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 coverage is 100%, so the baseline is 3, but the description adds provenance the schema lacks: it says where the repository id comes from (ha_hacs_list_repositories or ha_hacs_add_repository) and confirms the 'owner/repo' alternative. It does not elaborate on version or instance_id beyond the schema text.

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+resource ('Install or update a repository HACS already knows about') and immediately scopes it against siblings by naming the registration step (ha_hacs_add_repository) as the prior step. The phrase 'the step that actually writes its files into the config directory' tells the agent exactly what distinguishes this tool from the other ha_hacs_* 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?

Explicitly names the two sources for the repository id (ha_hacs_list_repositories or ha_hacs_add_repository), the implicit precondition that HACS must already know the repository, and the post-install requirement (restart for integrations/add-ons, not for plugin/theme/dashboard resources). It also states the required auth scope (ha:config).

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