What the person is looking at in TrailMark right now: the open document (path relative to the project), whether they are reading or editing it, the section on screen (heading path and line range), the text they selected (with its section and lines) and whether it has unsaved edits. Call this when the person says "this", "here", "the selected text", "this section", "what I'm reading" or otherwise points at something on their screen without naming it. Needs TrailMark open on the project with its agent connection on; otherwise it says so.

The comments the person left in TrailMark on passages of the project's Markdown documents ("this contradicts section 2", "simplify"). Each has an id, the document path, the quoted passage, its heading path and line, the comment text, when it was made, and state: anchored when the quote is still in the document (the line is where it is now), passageChanged when the passage was rewritten (the line is the best guess) or documentGone. Open comments by default; pass which = done or all for others. Call this when the person asks you to go through, address or apply their comments on the documents. A warning says when the comments file could not be read, which is why the list is empty. Also works when TrailMark is closed, from the project's files.

The notes the person chose to share with agents in TrailMark (its Notes window keeps their quick notes, drafts and prompts, and nothing in it is visible to you unless they shared that note). Each has note (its name, which read_note takes), title (its first line), when it was last changed and its size, newest first. Call this when the person points at their notes ("my note about the deploy", "the prompt I wrote", "what I jotted down"). A note that is not shared is not listed and cannot be read; you cannot list the notes folder. Also works when TrailMark is closed.

The tags in use in the project's Markdown documents: each tag with how many documents have it (count) and where it is written (from: frontMatter in the documents, trailmark added by the person in TrailMark, or both), most used first (the first 50; more says how many were left out), plus documents (how many Markdown documents there are) and untagged (how many have no tag), so you can tell whether tags are worth using here. Pass tag to list the documents that have it instead: each with its path, its one-line description (left out when it has none) and all of its tags (the first 20; total and more count the rest). limit asks for more or fewer. Use it to find the right documents in two calls in a large project: call list_tags (or search with tags) to narrow down, then read only the few documents that fit, instead of going through many search hits. Also works when TrailMark is closed, from the project's files.

The Markdown documents that changed since the person last read them in TrailMark, newest change first, with the time of the change. Call this when the person asks what changed, what they have not read yet, or to catch up (for example after you or another agent edited documents). Also works when TrailMark is closed, from the project's files.

Show the person a place in TrailMark: a document, optionally at a line or a heading. TrailMark opens it in its window without taking focus from your terminal, highlights the section and shows a notice with a way back; the person looks when ready. Use it after you wrote or found something they should see ("see the new section in docs/plan.md"). It starts TrailMark on the project if it is closed. It only shows; it never changes a document.

Read one of the notes the person shared with agents, by the note name that list_notes gives. Returns its title and its whole text. It only reads: it cannot change a note, and a note that is not shared is said not to exist. Also works when TrailMark is closed.

Mark one comment done after you addressed it, with an optional short reply saying what you did ("Rewritten in 3f2a1c"), which TrailMark shows under the comment. Use the id from list_comments. This is the only change an agent can make through TrailMark: it cannot write comments or edit documents. Also works when TrailMark is closed, on the project's files.

Find where something is described in the project's Markdown documents. Returns the best matching sections ranked, each with its path, heading path, line and a short snippet (the same index as TrailMark's Search everywhere), and the tags and description of its document when it has them. Use it to locate documentation before reading whole files, for example to find the section that defines a term or a decision. In a large project, narrow first: pass tags (see list_tags) to look only in the documents that have all of them, then read just the few that fit. Leave query out when you pass tags to get those documents (path, description, tags) instead of sections. Also works when TrailMark is closed, from the project's files.