add_subtitle

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

No annotations, so the description carries the full burden. It usefully discloses the input format (http(s) .srt link), the episode-vs-title scoping effect, and the LAN reachability constraint on where the subtitle appears. It omits persistence, failure behavior, and whether the addon must be installed/configured, leaving real behavioral gaps.

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?

Four short sentences, front-loaded with the core action and effect; every sentence adds information. Slightly loose line-break formatting but no filler.

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?

An output schema exists so return values needn't be described, and the mechanism/effect are covered. However, with 6 parameters at 0% schema coverage and no annotations, the definition leaves several params and failure/persistence behavior undocumented, so an agent cannot fully call it with confidence.

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 0%, so the description must compensate for all 6 params. It explains subtitle_url format and the season/episode semantics well, but says nothing about imdb_id, label, or language (whose non-obvious default 'heb' goes unexplained). Partial compensation only.

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 (serve/add) and resource (subtitle file for a title) and explains the delivery mechanism (MCP subtitle addon, Stremio picker). It is clearly distinct from list_subtitles/remove_subtitle, though it never explicitly distinguishes itself from the near-neighbor push_subtitle.

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?

Gives one conditional: use season/episode to target a single episode, omit them for whole-title coverage. It does not say when to prefer this over push_subtitle, auto_fetch_subtitle, or sync_addon, so the alternative selection is left to inference.

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